[Touch-packages] [Bug 1219337] Re: Users can change the clock without authenticating, allowing them to locally exploit sudo.
The Precise Pangolin has reached end of life, so this bug will not be fixed for that release ** Changed in: sudo (Ubuntu Precise) Status: Triaged => Won't Fix -- You received this bug notification because you are a member of Ubuntu Touch seeded packages, which is subscribed to policykit-desktop- privileges in Ubuntu. https://bugs.launchpad.net/bugs/1219337 Title: Users can change the clock without authenticating, allowing them to locally exploit sudo. Status in gnome-control-center: Confirmed Status in sudo: Unknown Status in policykit-desktop-privileges package in Ubuntu: Opinion Status in sudo package in Ubuntu: Fix Released Status in policykit-desktop-privileges source package in Precise: Opinion Status in sudo source package in Precise: Won't Fix Status in policykit-desktop-privileges source package in Trusty: Opinion Status in sudo source package in Trusty: Triaged Status in policykit-desktop-privileges source package in Utopic: Opinion Status in sudo source package in Utopic: Won't Fix Status in policykit-desktop-privileges source package in Vivid: Opinion Status in sudo source package in Vivid: Won't Fix Bug description: Under unity and cinnamon, it is possible for a user to turn off network-syncronized time and then change the time on the system. It is also possible to "cat /var/log/auth.log" and find the last time a user authenticated with sudo, along with which pty they used. If a user had used a terminal and successfully authenticated with sudo anytime in the past, and left the sudo file in "/var/lib/sudo//", a malicious user could walk up to an unlocked, logged in machine and gain sudo without knowing the password for the computer. To do this, a user would only need to launch a few terminals, figure out which pty they were on via "tty", find the an instance in /var/log/auth.log where sudo was used on that PTY, and set the clock to that time. Once this is done, they can run (for example) "sudo -s" and have a full access terminal. 1) This has been observed on Ubuntu 13.04, and may work on other versions. 2) This may have an effect on various window managers, but I confirmed it on Unity and Cinnamon 3) I expected to have to authenticate when I changed the time and date, as I do on Gnome and KDE. I also expected to be denied permission to auth.log 4) I was able to change the system time to whatever I wanted, and view auth.log. This was sufficient to access sudo without having to type my password. Note: This bug also affects any version of OS X, though the mechanism is different. Some versions don't require you to authenticate to change the time through the GUI, but some do. No version I've seen requires authentication to use the "systemsetup" command, which can alter the time from the command line. This may be an overall bug in sudo. Why can I bypass security by changing the time?! To manage notifications about this bug go to: https://bugs.launchpad.net/gnome-control-center/+bug/1219337/+subscriptions -- Mailing list: https://launchpad.net/~touch-packages Post to : touch-packages@lists.launchpad.net Unsubscribe : https://launchpad.net/~touch-packages More help : https://help.launchpad.net/ListHelp
[Touch-packages] [Bug 1219337] Re: Users can change the clock without authenticating, allowing them to locally exploit sudo.
** Changed in: gnome-control-center Status: Unknown => Confirmed ** Changed in: gnome-control-center Importance: Unknown => Medium -- You received this bug notification because you are a member of Ubuntu Touch seeded packages, which is subscribed to sudo in Ubuntu. https://bugs.launchpad.net/bugs/1219337 Title: Users can change the clock without authenticating, allowing them to locally exploit sudo. Status in gnome-control-center: Confirmed Status in sudo: Unknown Status in policykit-desktop-privileges package in Ubuntu: Opinion Status in sudo package in Ubuntu: Fix Released Status in policykit-desktop-privileges source package in Precise: Opinion Status in sudo source package in Precise: Triaged Status in policykit-desktop-privileges source package in Trusty: Opinion Status in sudo source package in Trusty: Triaged Status in policykit-desktop-privileges source package in Utopic: Opinion Status in sudo source package in Utopic: Won't Fix Status in policykit-desktop-privileges source package in Vivid: Opinion Status in sudo source package in Vivid: Won't Fix Bug description: Under unity and cinnamon, it is possible for a user to turn off network-syncronized time and then change the time on the system. It is also possible to "cat /var/log/auth.log" and find the last time a user authenticated with sudo, along with which pty they used. If a user had used a terminal and successfully authenticated with sudo anytime in the past, and left the sudo file in "/var/lib/sudo//", a malicious user could walk up to an unlocked, logged in machine and gain sudo without knowing the password for the computer. To do this, a user would only need to launch a few terminals, figure out which pty they were on via "tty", find the an instance in /var/log/auth.log where sudo was used on that PTY, and set the clock to that time. Once this is done, they can run (for example) "sudo -s" and have a full access terminal. 1) This has been observed on Ubuntu 13.04, and may work on other versions. 2) This may have an effect on various window managers, but I confirmed it on Unity and Cinnamon 3) I expected to have to authenticate when I changed the time and date, as I do on Gnome and KDE. I also expected to be denied permission to auth.log 4) I was able to change the system time to whatever I wanted, and view auth.log. This was sufficient to access sudo without having to type my password. Note: This bug also affects any version of OS X, though the mechanism is different. Some versions don't require you to authenticate to change the time through the GUI, but some do. No version I've seen requires authentication to use the "systemsetup" command, which can alter the time from the command line. This may be an overall bug in sudo. Why can I bypass security by changing the time?! To manage notifications about this bug go to: https://bugs.launchpad.net/gnome-control-center/+bug/1219337/+subscriptions -- Mailing list: https://launchpad.net/~touch-packages Post to : touch-packages@lists.launchpad.net Unsubscribe : https://launchpad.net/~touch-packages More help : https://help.launchpad.net/ListHelp
[Touch-packages] [Bug 1219337] Re: Users can change the clock without authenticating, allowing them to locally exploit sudo.
** Changed in: sudo (Ubuntu Vivid) Status: Triaged => Won't Fix ** CVE removed: http://www.cve.mitre.org/cgi- bin/cvename.cgi?name=2014-9680 ** CVE removed: http://www.cve.mitre.org/cgi- bin/cvename.cgi?name=2015-3757 ** Project changed: unity => ubuntu-translations ** No longer affects: ubuntu-translations -- You received this bug notification because you are a member of Ubuntu Touch seeded packages, which is subscribed to sudo in Ubuntu. https://bugs.launchpad.net/bugs/1219337 Title: Users can change the clock without authenticating, allowing them to locally exploit sudo. Status in gnome-control-center: Unknown Status in sudo: Unknown Status in policykit-desktop-privileges package in Ubuntu: Opinion Status in sudo package in Ubuntu: Fix Released Status in policykit-desktop-privileges source package in Precise: Opinion Status in sudo source package in Precise: Triaged Status in policykit-desktop-privileges source package in Trusty: Opinion Status in sudo source package in Trusty: Triaged Status in policykit-desktop-privileges source package in Utopic: Opinion Status in sudo source package in Utopic: Won't Fix Status in policykit-desktop-privileges source package in Vivid: Opinion Status in sudo source package in Vivid: Won't Fix Bug description: Under unity and cinnamon, it is possible for a user to turn off network-syncronized time and then change the time on the system. It is also possible to "cat /var/log/auth.log" and find the last time a user authenticated with sudo, along with which pty they used. If a user had used a terminal and successfully authenticated with sudo anytime in the past, and left the sudo file in "/var/lib/sudo//", a malicious user could walk up to an unlocked, logged in machine and gain sudo without knowing the password for the computer. To do this, a user would only need to launch a few terminals, figure out which pty they were on via "tty", find the an instance in /var/log/auth.log where sudo was used on that PTY, and set the clock to that time. Once this is done, they can run (for example) "sudo -s" and have a full access terminal. 1) This has been observed on Ubuntu 13.04, and may work on other versions. 2) This may have an effect on various window managers, but I confirmed it on Unity and Cinnamon 3) I expected to have to authenticate when I changed the time and date, as I do on Gnome and KDE. I also expected to be denied permission to auth.log 4) I was able to change the system time to whatever I wanted, and view auth.log. This was sufficient to access sudo without having to type my password. Note: This bug also affects any version of OS X, though the mechanism is different. Some versions don't require you to authenticate to change the time through the GUI, but some do. No version I've seen requires authentication to use the "systemsetup" command, which can alter the time from the command line. This may be an overall bug in sudo. Why can I bypass security by changing the time?! To manage notifications about this bug go to: https://bugs.launchpad.net/gnome-control-center/+bug/1219337/+subscriptions -- Mailing list: https://launchpad.net/~touch-packages Post to : touch-packages@lists.launchpad.net Unsubscribe : https://launchpad.net/~touch-packages More help : https://help.launchpad.net/ListHelp
[Touch-packages] [Bug 1219337] Re: Users can change the clock without authenticating, allowing them to locally exploit sudo.
utopic has seen the end of its life and is no longer receiving any updates. Marking the utopic task for this ticket as "Won't Fix". ** Changed in: sudo (Ubuntu Utopic) Status: Triaged => Won't Fix -- You received this bug notification because you are a member of Ubuntu Touch seeded packages, which is subscribed to sudo in Ubuntu. https://bugs.launchpad.net/bugs/1219337 Title: Users can change the clock without authenticating, allowing them to locally exploit sudo. Status in gnome-control-center: Unknown Status in sudo: Unknown Status in Unity: Invalid Status in policykit-desktop-privileges package in Ubuntu: Opinion Status in sudo package in Ubuntu: Fix Released Status in policykit-desktop-privileges source package in Precise: Opinion Status in sudo source package in Precise: Triaged Status in policykit-desktop-privileges source package in Trusty: Opinion Status in sudo source package in Trusty: Triaged Status in policykit-desktop-privileges source package in Utopic: Opinion Status in sudo source package in Utopic: Won't Fix Status in policykit-desktop-privileges source package in Vivid: Opinion Status in sudo source package in Vivid: Triaged Bug description: Under unity and cinnamon, it is possible for a user to turn off network-syncronized time and then change the time on the system. It is also possible to "cat /var/log/auth.log" and find the last time a user authenticated with sudo, along with which pty they used. If a user had used a terminal and successfully authenticated with sudo anytime in the past, and left the sudo file in "/var/lib/sudo//", a malicious user could walk up to an unlocked, logged in machine and gain sudo without knowing the password for the computer. To do this, a user would only need to launch a few terminals, figure out which pty they were on via "tty", find the an instance in /var/log/auth.log where sudo was used on that PTY, and set the clock to that time. Once this is done, they can run (for example) "sudo -s" and have a full access terminal. 1) This has been observed on Ubuntu 13.04, and may work on other versions. 2) This may have an effect on various window managers, but I confirmed it on Unity and Cinnamon 3) I expected to have to authenticate when I changed the time and date, as I do on Gnome and KDE. I also expected to be denied permission to auth.log 4) I was able to change the system time to whatever I wanted, and view auth.log. This was sufficient to access sudo without having to type my password. Note: This bug also affects any version of OS X, though the mechanism is different. Some versions don't require you to authenticate to change the time through the GUI, but some do. No version I've seen requires authentication to use the "systemsetup" command, which can alter the time from the command line. This may be an overall bug in sudo. Why can I bypass security by changing the time?! To manage notifications about this bug go to: https://bugs.launchpad.net/gnome-control-center/+bug/1219337/+subscriptions -- Mailing list: https://launchpad.net/~touch-packages Post to : touch-packages@lists.launchpad.net Unsubscribe : https://launchpad.net/~touch-packages More help : https://help.launchpad.net/ListHelp
[Touch-packages] [Bug 1219337] Re: Users can change the clock without authenticating, allowing them to locally exploit sudo.
It looks like sudo 1.8.12 made it into 15.10 finally. Excellent. Apple went the other route and locked the clock back down. (https://support.apple.com/en-us/HT205031) The CVE associated with this bug seems to be about the TZ (seen on RedHat's security site: https://access.redhat.com/security/cve/CVE-2014-9680). Apple's CVE is about restricting access to the time settings (http://www.cve.mitre.org /cgi-bin/cvename.cgi?name=CVE-2015-3757). I don't think either one really reflects this bug. ** CVE added: http://www.cve.mitre.org/cgi- bin/cvename.cgi?name=2015-3757 -- You received this bug notification because you are a member of Ubuntu Touch seeded packages, which is subscribed to sudo in Ubuntu. https://bugs.launchpad.net/bugs/1219337 Title: Users can change the clock without authenticating, allowing them to locally exploit sudo. Status in gnome-control-center: Unknown Status in sudo: Unknown Status in Unity: Invalid Status in policykit-desktop-privileges package in Ubuntu: Opinion Status in sudo package in Ubuntu: Fix Released Status in policykit-desktop-privileges source package in Precise: Opinion Status in sudo source package in Precise: Triaged Status in policykit-desktop-privileges source package in Trusty: Opinion Status in sudo source package in Trusty: Triaged Status in policykit-desktop-privileges source package in Utopic: Opinion Status in sudo source package in Utopic: Triaged Status in policykit-desktop-privileges source package in Vivid: Opinion Status in sudo source package in Vivid: Triaged Bug description: Under unity and cinnamon, it is possible for a user to turn off network-syncronized time and then change the time on the system. It is also possible to "cat /var/log/auth.log" and find the last time a user authenticated with sudo, along with which pty they used. If a user had used a terminal and successfully authenticated with sudo anytime in the past, and left the sudo file in "/var/lib/sudo//", a malicious user could walk up to an unlocked, logged in machine and gain sudo without knowing the password for the computer. To do this, a user would only need to launch a few terminals, figure out which pty they were on via "tty", find the an instance in /var/log/auth.log where sudo was used on that PTY, and set the clock to that time. Once this is done, they can run (for example) "sudo -s" and have a full access terminal. 1) This has been observed on Ubuntu 13.04, and may work on other versions. 2) This may have an effect on various window managers, but I confirmed it on Unity and Cinnamon 3) I expected to have to authenticate when I changed the time and date, as I do on Gnome and KDE. I also expected to be denied permission to auth.log 4) I was able to change the system time to whatever I wanted, and view auth.log. This was sufficient to access sudo without having to type my password. Note: This bug also affects any version of OS X, though the mechanism is different. Some versions don't require you to authenticate to change the time through the GUI, but some do. No version I've seen requires authentication to use the "systemsetup" command, which can alter the time from the command line. This may be an overall bug in sudo. Why can I bypass security by changing the time?! To manage notifications about this bug go to: https://bugs.launchpad.net/gnome-control-center/+bug/1219337/+subscriptions -- Mailing list: https://launchpad.net/~touch-packages Post to : touch-packages@lists.launchpad.net Unsubscribe : https://launchpad.net/~touch-packages More help : https://help.launchpad.net/ListHelp
[Touch-packages] [Bug 1219337] Re: Users can change the clock without authenticating, allowing them to locally exploit sudo.
FYI, the current plan is to wait until Debian bug #786555 gets fixed, and then publish updates for stable Ubuntu releases based on the jessie sudo package. -- You received this bug notification because you are a member of Ubuntu Touch seeded packages, which is subscribed to sudo in Ubuntu. https://bugs.launchpad.net/bugs/1219337 Title: Users can change the clock without authenticating, allowing them to locally exploit sudo. Status in GNOME Control Center: Unknown Status in sudo: Unknown Status in Unity: Invalid Status in policykit-desktop-privileges package in Ubuntu: Opinion Status in sudo package in Ubuntu: Fix Released Status in policykit-desktop-privileges source package in Precise: Opinion Status in sudo source package in Precise: Triaged Status in policykit-desktop-privileges source package in Trusty: Opinion Status in sudo source package in Trusty: Triaged Status in policykit-desktop-privileges source package in Utopic: Opinion Status in sudo source package in Utopic: Triaged Status in policykit-desktop-privileges source package in Vivid: Opinion Status in sudo source package in Vivid: Triaged Bug description: Under unity and cinnamon, it is possible for a user to turn off network-syncronized time and then change the time on the system. It is also possible to "cat /var/log/auth.log" and find the last time a user authenticated with sudo, along with which pty they used. If a user had used a terminal and successfully authenticated with sudo anytime in the past, and left the sudo file in "/var/lib/sudo//", a malicious user could walk up to an unlocked, logged in machine and gain sudo without knowing the password for the computer. To do this, a user would only need to launch a few terminals, figure out which pty they were on via "tty", find the an instance in /var/log/auth.log where sudo was used on that PTY, and set the clock to that time. Once this is done, they can run (for example) "sudo -s" and have a full access terminal. 1) This has been observed on Ubuntu 13.04, and may work on other versions. 2) This may have an effect on various window managers, but I confirmed it on Unity and Cinnamon 3) I expected to have to authenticate when I changed the time and date, as I do on Gnome and KDE. I also expected to be denied permission to auth.log 4) I was able to change the system time to whatever I wanted, and view auth.log. This was sufficient to access sudo without having to type my password. Note: This bug also affects any version of OS X, though the mechanism is different. Some versions don't require you to authenticate to change the time through the GUI, but some do. No version I've seen requires authentication to use the "systemsetup" command, which can alter the time from the command line. This may be an overall bug in sudo. Why can I bypass security by changing the time?! To manage notifications about this bug go to: https://bugs.launchpad.net/gnome-control-center/+bug/1219337/+subscriptions -- Mailing list: https://launchpad.net/~touch-packages Post to : touch-packages@lists.launchpad.net Unsubscribe : https://launchpad.net/~touch-packages More help : https://help.launchpad.net/ListHelp
[Touch-packages] [Bug 1219337] Re: Users can change the clock without authenticating, allowing them to locally exploit sudo.
** Branch linked: lp:ubuntu/sudo -- You received this bug notification because you are a member of Ubuntu Touch seeded packages, which is subscribed to sudo in Ubuntu. https://bugs.launchpad.net/bugs/1219337 Title: Users can change the clock without authenticating, allowing them to locally exploit sudo. Status in GNOME Control Center: Unknown Status in sudo: Unknown Status in Unity: Invalid Status in policykit-desktop-privileges package in Ubuntu: Opinion Status in sudo package in Ubuntu: Fix Released Status in policykit-desktop-privileges source package in Precise: Opinion Status in sudo source package in Precise: Triaged Status in policykit-desktop-privileges source package in Trusty: Opinion Status in sudo source package in Trusty: Triaged Status in policykit-desktop-privileges source package in Utopic: Opinion Status in sudo source package in Utopic: Triaged Status in policykit-desktop-privileges source package in Vivid: Opinion Status in sudo source package in Vivid: Triaged Bug description: Under unity and cinnamon, it is possible for a user to turn off network-syncronized time and then change the time on the system. It is also possible to "cat /var/log/auth.log" and find the last time a user authenticated with sudo, along with which pty they used. If a user had used a terminal and successfully authenticated with sudo anytime in the past, and left the sudo file in "/var/lib/sudo//", a malicious user could walk up to an unlocked, logged in machine and gain sudo without knowing the password for the computer. To do this, a user would only need to launch a few terminals, figure out which pty they were on via "tty", find the an instance in /var/log/auth.log where sudo was used on that PTY, and set the clock to that time. Once this is done, they can run (for example) "sudo -s" and have a full access terminal. 1) This has been observed on Ubuntu 13.04, and may work on other versions. 2) This may have an effect on various window managers, but I confirmed it on Unity and Cinnamon 3) I expected to have to authenticate when I changed the time and date, as I do on Gnome and KDE. I also expected to be denied permission to auth.log 4) I was able to change the system time to whatever I wanted, and view auth.log. This was sufficient to access sudo without having to type my password. Note: This bug also affects any version of OS X, though the mechanism is different. Some versions don't require you to authenticate to change the time through the GUI, but some do. No version I've seen requires authentication to use the "systemsetup" command, which can alter the time from the command line. This may be an overall bug in sudo. Why can I bypass security by changing the time?! To manage notifications about this bug go to: https://bugs.launchpad.net/gnome-control-center/+bug/1219337/+subscriptions -- Mailing list: https://launchpad.net/~touch-packages Post to : touch-packages@lists.launchpad.net Unsubscribe : https://launchpad.net/~touch-packages More help : https://help.launchpad.net/ListHelp
[Touch-packages] [Bug 1219337] Re: Users can change the clock without authenticating, allowing them to locally exploit sudo.
This bug was fixed in the package sudo - 1.8.12-1ubuntu1 --- sudo (1.8.12-1ubuntu1) wily; urgency=medium * Merge from Debian unstable. (LP: #1451274, LP: #1219337) Remaining changes: - debian/rules: + compile with --without-lecture --with-tty-tickets --enable-admin-flag + install man/man8/sudo_root.8 in both flavours + install apport hooks - debian/sudoers: + also grant admin group sudo access - debian/source_sudo.py, debian/sudo-ldap.dirs, debian/sudo.dirs: + add usr/share/apport/package-hooks - debian/sudo.pam: + Use pam_env to read /etc/environment and /etc/default/locale environment files. Reading ~/.pam_environment is not permitted due to security reasons. - debian/control: + dh-autoreconf dependency fixes missing-build-dependency-for-dh_-command - Remaining patches: + keep_home_by_default.patch: Keep HOME in the default environment + debian/patches/also_check_sudo_group.diff: also check the sudo group in plugins/sudoers/sudoers.c to create the admin flag file. Leave the admin group check for backwards compatibility. * Dropped patches no longer needed: + add_probe_interfaces_setting.diff + actually-use-buildflags.diff + CVE-2014-9680.patch sudo (1.8.12-1) unstable; urgency=low * new upstream version, closes: #772707, #773383 * patch from Christian Kastner to fix sudoers handling error when moving between sudo and sudo-ldap packages, closes: #776137 sudo (1.8.11p2-1) unstable; urgency=low * new upstream version sudo (1.8.11p1-2) unstable; urgency=low * patch from Jakub Wilk to fix 'ignoring time stamp from the future' messages, closes: #762465 * upstream patch forwarded by Laurent Bigonville that fixes problem with Linux kernel auditing code, closes: #764817 sudo (1.8.11p1-1) unstable; urgency=low * new upstream version, closes: #764286 * fix typo in German translation, closes: #761601 sudo (1.8.10p3-1) unstable; urgency=low * new upstream release * add hardening=+all to match login and su * updated VCS URLs and crypto verified watch file, closes: #747473 * harmonize configure options for LDAP version to match non-LDAP version, in particular stop using --with-secure-path and add configure_args * enable audit support on Linux systems, closes: #745779 * follow upstream change from --with-timedir to --with-rundir -- Marc Deslauriers Wed, 13 May 2015 15:43:49 -0400 ** Changed in: sudo (Ubuntu) Status: Triaged => Fix Released ** CVE added: http://www.cve.mitre.org/cgi- bin/cvename.cgi?name=2014-9680 -- You received this bug notification because you are a member of Ubuntu Touch seeded packages, which is subscribed to sudo in Ubuntu. https://bugs.launchpad.net/bugs/1219337 Title: Users can change the clock without authenticating, allowing them to locally exploit sudo. Status in GNOME Control Center: Unknown Status in sudo: Unknown Status in Unity: Invalid Status in policykit-desktop-privileges package in Ubuntu: Opinion Status in sudo package in Ubuntu: Fix Released Status in policykit-desktop-privileges source package in Precise: Opinion Status in sudo source package in Precise: Triaged Status in policykit-desktop-privileges source package in Trusty: Opinion Status in sudo source package in Trusty: Triaged Status in policykit-desktop-privileges source package in Utopic: Opinion Status in sudo source package in Utopic: Triaged Status in policykit-desktop-privileges source package in Vivid: Opinion Status in sudo source package in Vivid: Triaged Bug description: Under unity and cinnamon, it is possible for a user to turn off network-syncronized time and then change the time on the system. It is also possible to "cat /var/log/auth.log" and find the last time a user authenticated with sudo, along with which pty they used. If a user had used a terminal and successfully authenticated with sudo anytime in the past, and left the sudo file in "/var/lib/sudo//", a malicious user could walk up to an unlocked, logged in machine and gain sudo without knowing the password for the computer. To do this, a user would only need to launch a few terminals, figure out which pty they were on via "tty", find the an instance in /var/log/auth.log where sudo was used on that PTY, and set the clock to that time. Once this is done, they can run (for example) "sudo -s" and have a full access terminal. 1) This has been observed on Ubuntu 13.04, and may work on other versions. 2) This may have an effect on various window managers, but I confirmed it on Unity and Cinnamon 3) I expected to have to authenticate when I changed the time and date, as I do on Gnome and KDE. I also expected to be denied permission to auth.log 4) I was able to change the system time to whatever I wanted, and view auth.log. This was sufficient to access sudo without having to type
[Touch-packages] [Bug 1219337] Re: Users can change the clock without authenticating, allowing them to locally exploit sudo.
> You can set the time with: > timedatectl set-time "2000-01-01 10:00:00" Wow. Yeah, that'll make exploiting this *much* easier on desktop. Fortunately Ubuntu Server doesn't allow this without authenticating. -- You received this bug notification because you are a member of Ubuntu Touch seeded packages, which is subscribed to sudo in Ubuntu. https://bugs.launchpad.net/bugs/1219337 Title: Users can change the clock without authenticating, allowing them to locally exploit sudo. Status in GNOME Control Center: Unknown Status in sudo: Unknown Status in Unity: Invalid Status in policykit-desktop-privileges package in Ubuntu: Opinion Status in sudo package in Ubuntu: Triaged Status in policykit-desktop-privileges source package in Precise: Opinion Status in sudo source package in Precise: Triaged Status in policykit-desktop-privileges source package in Trusty: Opinion Status in sudo source package in Trusty: Triaged Status in policykit-desktop-privileges source package in Utopic: Opinion Status in sudo source package in Utopic: Triaged Status in policykit-desktop-privileges source package in Vivid: Opinion Status in sudo source package in Vivid: Triaged Bug description: Under unity and cinnamon, it is possible for a user to turn off network-syncronized time and then change the time on the system. It is also possible to "cat /var/log/auth.log" and find the last time a user authenticated with sudo, along with which pty they used. If a user had used a terminal and successfully authenticated with sudo anytime in the past, and left the sudo file in "/var/lib/sudo//", a malicious user could walk up to an unlocked, logged in machine and gain sudo without knowing the password for the computer. To do this, a user would only need to launch a few terminals, figure out which pty they were on via "tty", find the an instance in /var/log/auth.log where sudo was used on that PTY, and set the clock to that time. Once this is done, they can run (for example) "sudo -s" and have a full access terminal. 1) This has been observed on Ubuntu 13.04, and may work on other versions. 2) This may have an effect on various window managers, but I confirmed it on Unity and Cinnamon 3) I expected to have to authenticate when I changed the time and date, as I do on Gnome and KDE. I also expected to be denied permission to auth.log 4) I was able to change the system time to whatever I wanted, and view auth.log. This was sufficient to access sudo without having to type my password. Note: This bug also affects any version of OS X, though the mechanism is different. Some versions don't require you to authenticate to change the time through the GUI, but some do. No version I've seen requires authentication to use the "systemsetup" command, which can alter the time from the command line. This may be an overall bug in sudo. Why can I bypass security by changing the time?! To manage notifications about this bug go to: https://bugs.launchpad.net/gnome-control-center/+bug/1219337/+subscriptions -- Mailing list: https://launchpad.net/~touch-packages Post to : touch-packages@lists.launchpad.net Unsubscribe : https://launchpad.net/~touch-packages More help : https://help.launchpad.net/ListHelp
[Touch-packages] [Bug 1219337] Re: Users can change the clock without authenticating, allowing them to locally exploit sudo.
Serious question: I understand that this is consider a low priority issue, but how hard is to update sudo? why can't it just be pushed with the next update? -- You received this bug notification because you are a member of Ubuntu Touch seeded packages, which is subscribed to sudo in Ubuntu. https://bugs.launchpad.net/bugs/1219337 Title: Users can change the clock without authenticating, allowing them to locally exploit sudo. Status in GNOME Control Center: Unknown Status in sudo: Unknown Status in Unity: Invalid Status in policykit-desktop-privileges package in Ubuntu: Opinion Status in sudo package in Ubuntu: Triaged Status in policykit-desktop-privileges source package in Precise: Opinion Status in sudo source package in Precise: Triaged Status in policykit-desktop-privileges source package in Trusty: Opinion Status in sudo source package in Trusty: Triaged Status in policykit-desktop-privileges source package in Utopic: Opinion Status in sudo source package in Utopic: Triaged Status in policykit-desktop-privileges source package in Vivid: Opinion Status in sudo source package in Vivid: Triaged Bug description: Under unity and cinnamon, it is possible for a user to turn off network-syncronized time and then change the time on the system. It is also possible to "cat /var/log/auth.log" and find the last time a user authenticated with sudo, along with which pty they used. If a user had used a terminal and successfully authenticated with sudo anytime in the past, and left the sudo file in "/var/lib/sudo//", a malicious user could walk up to an unlocked, logged in machine and gain sudo without knowing the password for the computer. To do this, a user would only need to launch a few terminals, figure out which pty they were on via "tty", find the an instance in /var/log/auth.log where sudo was used on that PTY, and set the clock to that time. Once this is done, they can run (for example) "sudo -s" and have a full access terminal. 1) This has been observed on Ubuntu 13.04, and may work on other versions. 2) This may have an effect on various window managers, but I confirmed it on Unity and Cinnamon 3) I expected to have to authenticate when I changed the time and date, as I do on Gnome and KDE. I also expected to be denied permission to auth.log 4) I was able to change the system time to whatever I wanted, and view auth.log. This was sufficient to access sudo without having to type my password. Note: This bug also affects any version of OS X, though the mechanism is different. Some versions don't require you to authenticate to change the time through the GUI, but some do. No version I've seen requires authentication to use the "systemsetup" command, which can alter the time from the command line. This may be an overall bug in sudo. Why can I bypass security by changing the time?! To manage notifications about this bug go to: https://bugs.launchpad.net/gnome-control-center/+bug/1219337/+subscriptions -- Mailing list: https://launchpad.net/~touch-packages Post to : touch-packages@lists.launchpad.net Unsubscribe : https://launchpad.net/~touch-packages More help : https://help.launchpad.net/ListHelp
[Touch-packages] [Bug 1219337] Re: Users can change the clock without authenticating, allowing them to locally exploit sudo.
Oh, nevermind! You're talking about outside of the sudo instance. In the case of Cron, etc: just let *the user* decide whether they want to be asked after the first time. Make it an option to unlock the clock, disabled by default but still available. -- You received this bug notification because you are a member of Ubuntu Touch seeded packages, which is subscribed to sudo in Ubuntu. https://bugs.launchpad.net/bugs/1219337 Title: Users can change the clock without authenticating, allowing them to locally exploit sudo. Status in GNOME Control Center: Unknown Status in sudo: Unknown Status in Unity: Invalid Status in policykit-desktop-privileges package in Ubuntu: Opinion Status in sudo package in Ubuntu: Triaged Status in policykit-desktop-privileges source package in Precise: Opinion Status in sudo source package in Precise: Triaged Status in policykit-desktop-privileges source package in Trusty: Opinion Status in sudo source package in Trusty: Triaged Status in policykit-desktop-privileges source package in Utopic: Opinion Status in sudo source package in Utopic: Triaged Status in policykit-desktop-privileges source package in Vivid: Opinion Status in sudo source package in Vivid: Triaged Bug description: Under unity and cinnamon, it is possible for a user to turn off network-syncronized time and then change the time on the system. It is also possible to "cat /var/log/auth.log" and find the last time a user authenticated with sudo, along with which pty they used. If a user had used a terminal and successfully authenticated with sudo anytime in the past, and left the sudo file in "/var/lib/sudo//", a malicious user could walk up to an unlocked, logged in machine and gain sudo without knowing the password for the computer. To do this, a user would only need to launch a few terminals, figure out which pty they were on via "tty", find the an instance in /var/log/auth.log where sudo was used on that PTY, and set the clock to that time. Once this is done, they can run (for example) "sudo -s" and have a full access terminal. 1) This has been observed on Ubuntu 13.04, and may work on other versions. 2) This may have an effect on various window managers, but I confirmed it on Unity and Cinnamon 3) I expected to have to authenticate when I changed the time and date, as I do on Gnome and KDE. I also expected to be denied permission to auth.log 4) I was able to change the system time to whatever I wanted, and view auth.log. This was sufficient to access sudo without having to type my password. Note: This bug also affects any version of OS X, though the mechanism is different. Some versions don't require you to authenticate to change the time through the GUI, but some do. No version I've seen requires authentication to use the "systemsetup" command, which can alter the time from the command line. This may be an overall bug in sudo. Why can I bypass security by changing the time?! To manage notifications about this bug go to: https://bugs.launchpad.net/gnome-control-center/+bug/1219337/+subscriptions -- Mailing list: https://launchpad.net/~touch-packages Post to : touch-packages@lists.launchpad.net Unsubscribe : https://launchpad.net/~touch-packages More help : https://help.launchpad.net/ListHelp
[Touch-packages] [Bug 1219337] Re: Users can change the clock without authenticating, allowing them to locally exploit sudo.
Kay, the update to sudo (1.8.10) actually solves this by using the monotonic clock. All that needs to happen is for Ubuntu to udpate to it. :) -- You received this bug notification because you are a member of Ubuntu Touch seeded packages, which is subscribed to sudo in Ubuntu. https://bugs.launchpad.net/bugs/1219337 Title: Users can change the clock without authenticating, allowing them to locally exploit sudo. Status in GNOME Control Center: Unknown Status in sudo: Unknown Status in Unity: Invalid Status in policykit-desktop-privileges package in Ubuntu: Opinion Status in sudo package in Ubuntu: Triaged Status in policykit-desktop-privileges source package in Precise: Opinion Status in sudo source package in Precise: Triaged Status in policykit-desktop-privileges source package in Trusty: Opinion Status in sudo source package in Trusty: Triaged Status in policykit-desktop-privileges source package in Utopic: Opinion Status in sudo source package in Utopic: Triaged Status in policykit-desktop-privileges source package in Vivid: Opinion Status in sudo source package in Vivid: Triaged Bug description: Under unity and cinnamon, it is possible for a user to turn off network-syncronized time and then change the time on the system. It is also possible to "cat /var/log/auth.log" and find the last time a user authenticated with sudo, along with which pty they used. If a user had used a terminal and successfully authenticated with sudo anytime in the past, and left the sudo file in "/var/lib/sudo//", a malicious user could walk up to an unlocked, logged in machine and gain sudo without knowing the password for the computer. To do this, a user would only need to launch a few terminals, figure out which pty they were on via "tty", find the an instance in /var/log/auth.log where sudo was used on that PTY, and set the clock to that time. Once this is done, they can run (for example) "sudo -s" and have a full access terminal. 1) This has been observed on Ubuntu 13.04, and may work on other versions. 2) This may have an effect on various window managers, but I confirmed it on Unity and Cinnamon 3) I expected to have to authenticate when I changed the time and date, as I do on Gnome and KDE. I also expected to be denied permission to auth.log 4) I was able to change the system time to whatever I wanted, and view auth.log. This was sufficient to access sudo without having to type my password. Note: This bug also affects any version of OS X, though the mechanism is different. Some versions don't require you to authenticate to change the time through the GUI, but some do. No version I've seen requires authentication to use the "systemsetup" command, which can alter the time from the command line. This may be an overall bug in sudo. Why can I bypass security by changing the time?! To manage notifications about this bug go to: https://bugs.launchpad.net/gnome-control-center/+bug/1219337/+subscriptions -- Mailing list: https://launchpad.net/~touch-packages Post to : touch-packages@lists.launchpad.net Unsubscribe : https://launchpad.net/~touch-packages More help : https://help.launchpad.net/ListHelp
[Touch-packages] [Bug 1219337] Re: Users can change the clock without authenticating, allowing them to locally exploit sudo.
A solution could be setting one clock for users, which can be set to their prefered timezone and one for the system (root) which is used by cron jobs etc -- You received this bug notification because you are a member of Ubuntu Touch seeded packages, which is subscribed to sudo in Ubuntu. https://bugs.launchpad.net/bugs/1219337 Title: Users can change the clock without authenticating, allowing them to locally exploit sudo. Status in GNOME Control Center: Unknown Status in sudo: Unknown Status in Unity: Invalid Status in policykit-desktop-privileges package in Ubuntu: Opinion Status in sudo package in Ubuntu: Triaged Status in policykit-desktop-privileges source package in Precise: Opinion Status in sudo source package in Precise: Triaged Status in policykit-desktop-privileges source package in Trusty: Opinion Status in sudo source package in Trusty: Triaged Status in policykit-desktop-privileges source package in Utopic: Opinion Status in sudo source package in Utopic: Triaged Status in policykit-desktop-privileges source package in Vivid: Opinion Status in sudo source package in Vivid: Triaged Bug description: Under unity and cinnamon, it is possible for a user to turn off network-syncronized time and then change the time on the system. It is also possible to "cat /var/log/auth.log" and find the last time a user authenticated with sudo, along with which pty they used. If a user had used a terminal and successfully authenticated with sudo anytime in the past, and left the sudo file in "/var/lib/sudo//", a malicious user could walk up to an unlocked, logged in machine and gain sudo without knowing the password for the computer. To do this, a user would only need to launch a few terminals, figure out which pty they were on via "tty", find the an instance in /var/log/auth.log where sudo was used on that PTY, and set the clock to that time. Once this is done, they can run (for example) "sudo -s" and have a full access terminal. 1) This has been observed on Ubuntu 13.04, and may work on other versions. 2) This may have an effect on various window managers, but I confirmed it on Unity and Cinnamon 3) I expected to have to authenticate when I changed the time and date, as I do on Gnome and KDE. I also expected to be denied permission to auth.log 4) I was able to change the system time to whatever I wanted, and view auth.log. This was sufficient to access sudo without having to type my password. Note: This bug also affects any version of OS X, though the mechanism is different. Some versions don't require you to authenticate to change the time through the GUI, but some do. No version I've seen requires authentication to use the "systemsetup" command, which can alter the time from the command line. This may be an overall bug in sudo. Why can I bypass security by changing the time?! To manage notifications about this bug go to: https://bugs.launchpad.net/gnome-control-center/+bug/1219337/+subscriptions -- Mailing list: https://launchpad.net/~touch-packages Post to : touch-packages@lists.launchpad.net Unsubscribe : https://launchpad.net/~touch-packages More help : https://help.launchpad.net/ListHelp
[Touch-packages] [Bug 1219337] Re: Users can change the clock without authenticating, allowing them to locally exploit sudo.
You can set the time with: timedatectl set-time "2000-01-01 10:00:00" -- You received this bug notification because you are a member of Ubuntu Touch seeded packages, which is subscribed to sudo in Ubuntu. https://bugs.launchpad.net/bugs/1219337 Title: Users can change the clock without authenticating, allowing them to locally exploit sudo. Status in GNOME Control Center: Unknown Status in sudo: Unknown Status in Unity: Invalid Status in policykit-desktop-privileges package in Ubuntu: Opinion Status in sudo package in Ubuntu: Triaged Status in policykit-desktop-privileges source package in Precise: Opinion Status in sudo source package in Precise: Triaged Status in policykit-desktop-privileges source package in Trusty: Opinion Status in sudo source package in Trusty: Triaged Status in policykit-desktop-privileges source package in Utopic: Opinion Status in sudo source package in Utopic: Triaged Status in policykit-desktop-privileges source package in Vivid: Opinion Status in sudo source package in Vivid: Triaged Bug description: Under unity and cinnamon, it is possible for a user to turn off network-syncronized time and then change the time on the system. It is also possible to "cat /var/log/auth.log" and find the last time a user authenticated with sudo, along with which pty they used. If a user had used a terminal and successfully authenticated with sudo anytime in the past, and left the sudo file in "/var/lib/sudo//", a malicious user could walk up to an unlocked, logged in machine and gain sudo without knowing the password for the computer. To do this, a user would only need to launch a few terminals, figure out which pty they were on via "tty", find the an instance in /var/log/auth.log where sudo was used on that PTY, and set the clock to that time. Once this is done, they can run (for example) "sudo -s" and have a full access terminal. 1) This has been observed on Ubuntu 13.04, and may work on other versions. 2) This may have an effect on various window managers, but I confirmed it on Unity and Cinnamon 3) I expected to have to authenticate when I changed the time and date, as I do on Gnome and KDE. I also expected to be denied permission to auth.log 4) I was able to change the system time to whatever I wanted, and view auth.log. This was sufficient to access sudo without having to type my password. Note: This bug also affects any version of OS X, though the mechanism is different. Some versions don't require you to authenticate to change the time through the GUI, but some do. No version I've seen requires authentication to use the "systemsetup" command, which can alter the time from the command line. This may be an overall bug in sudo. Why can I bypass security by changing the time?! To manage notifications about this bug go to: https://bugs.launchpad.net/gnome-control-center/+bug/1219337/+subscriptions -- Mailing list: https://launchpad.net/~touch-packages Post to : touch-packages@lists.launchpad.net Unsubscribe : https://launchpad.net/~touch-packages More help : https://help.launchpad.net/ListHelp
[Touch-packages] [Bug 1219337] Re: Users can change the clock without authenticating, allowing them to locally exploit sudo.
Indeed. Trojaning those requires waiting for the user. Why lay a trap and wait when you can just break down the door? If I can use dogtail or similar to automate the clock and suddenly we're in drive-by territory. -- You received this bug notification because you are a member of Ubuntu Touch seeded packages, which is subscribed to sudo in Ubuntu. https://bugs.launchpad.net/bugs/1219337 Title: Users can change the clock without authenticating, allowing them to locally exploit sudo. Status in GNOME Control Center: Unknown Status in sudo: Unknown Status in Unity: Invalid Status in policykit-desktop-privileges package in Ubuntu: Opinion Status in sudo package in Ubuntu: Triaged Status in policykit-desktop-privileges source package in Precise: Opinion Status in sudo source package in Precise: Triaged Status in policykit-desktop-privileges source package in Trusty: Opinion Status in sudo source package in Trusty: Triaged Status in policykit-desktop-privileges source package in Utopic: Opinion Status in sudo source package in Utopic: Triaged Status in policykit-desktop-privileges source package in Vivid: Opinion Status in sudo source package in Vivid: Triaged Bug description: Under unity and cinnamon, it is possible for a user to turn off network-syncronized time and then change the time on the system. It is also possible to "cat /var/log/auth.log" and find the last time a user authenticated with sudo, along with which pty they used. If a user had used a terminal and successfully authenticated with sudo anytime in the past, and left the sudo file in "/var/lib/sudo//", a malicious user could walk up to an unlocked, logged in machine and gain sudo without knowing the password for the computer. To do this, a user would only need to launch a few terminals, figure out which pty they were on via "tty", find the an instance in /var/log/auth.log where sudo was used on that PTY, and set the clock to that time. Once this is done, they can run (for example) "sudo -s" and have a full access terminal. 1) This has been observed on Ubuntu 13.04, and may work on other versions. 2) This may have an effect on various window managers, but I confirmed it on Unity and Cinnamon 3) I expected to have to authenticate when I changed the time and date, as I do on Gnome and KDE. I also expected to be denied permission to auth.log 4) I was able to change the system time to whatever I wanted, and view auth.log. This was sufficient to access sudo without having to type my password. Note: This bug also affects any version of OS X, though the mechanism is different. Some versions don't require you to authenticate to change the time through the GUI, but some do. No version I've seen requires authentication to use the "systemsetup" command, which can alter the time from the command line. This may be an overall bug in sudo. Why can I bypass security by changing the time?! To manage notifications about this bug go to: https://bugs.launchpad.net/gnome-control-center/+bug/1219337/+subscriptions -- Mailing list: https://launchpad.net/~touch-packages Post to : touch-packages@lists.launchpad.net Unsubscribe : https://launchpad.net/~touch-packages More help : https://help.launchpad.net/ListHelp
[Touch-packages] [Bug 1219337] Re: Users can change the clock without authenticating, allowing them to locally exploit sudo.
Should be pretty trivial, and slightly more amusing than simply trojaning ~/.bash* or ~/bin/sudo. For completeness' sake, perhaps it could also do the same for the polkit timestamp files also. -- You received this bug notification because you are a member of Ubuntu Touch seeded packages, which is subscribed to sudo in Ubuntu. https://bugs.launchpad.net/bugs/1219337 Title: Users can change the clock without authenticating, allowing them to locally exploit sudo. Status in GNOME Control Center: Unknown Status in sudo: Unknown Status in Unity: Invalid Status in policykit-desktop-privileges package in Ubuntu: Opinion Status in sudo package in Ubuntu: Triaged Status in policykit-desktop-privileges source package in Precise: Opinion Status in sudo source package in Precise: Triaged Status in policykit-desktop-privileges source package in Trusty: Opinion Status in sudo source package in Trusty: Triaged Status in policykit-desktop-privileges source package in Utopic: Opinion Status in sudo source package in Utopic: Triaged Status in policykit-desktop-privileges source package in Vivid: Opinion Status in sudo source package in Vivid: Triaged Bug description: Under unity and cinnamon, it is possible for a user to turn off network-syncronized time and then change the time on the system. It is also possible to "cat /var/log/auth.log" and find the last time a user authenticated with sudo, along with which pty they used. If a user had used a terminal and successfully authenticated with sudo anytime in the past, and left the sudo file in "/var/lib/sudo//", a malicious user could walk up to an unlocked, logged in machine and gain sudo without knowing the password for the computer. To do this, a user would only need to launch a few terminals, figure out which pty they were on via "tty", find the an instance in /var/log/auth.log where sudo was used on that PTY, and set the clock to that time. Once this is done, they can run (for example) "sudo -s" and have a full access terminal. 1) This has been observed on Ubuntu 13.04, and may work on other versions. 2) This may have an effect on various window managers, but I confirmed it on Unity and Cinnamon 3) I expected to have to authenticate when I changed the time and date, as I do on Gnome and KDE. I also expected to be denied permission to auth.log 4) I was able to change the system time to whatever I wanted, and view auth.log. This was sufficient to access sudo without having to type my password. Note: This bug also affects any version of OS X, though the mechanism is different. Some versions don't require you to authenticate to change the time through the GUI, but some do. No version I've seen requires authentication to use the "systemsetup" command, which can alter the time from the command line. This may be an overall bug in sudo. Why can I bypass security by changing the time?! To manage notifications about this bug go to: https://bugs.launchpad.net/gnome-control-center/+bug/1219337/+subscriptions -- Mailing list: https://launchpad.net/~touch-packages Post to : touch-packages@lists.launchpad.net Unsubscribe : https://launchpad.net/~touch-packages More help : https://help.launchpad.net/ListHelp
[Touch-packages] [Bug 1219337] Re: Users can change the clock without authenticating, allowing them to locally exploit sudo.
Yup, I think so. while true; do setsid ; done; or the like. In my tests rolling through then all took about 5 minutes, and that was in a crappy VM with 1 core and 30% CPU being used by compiz. I haven't gotten it to pop an escalated shell yet, but I'll poke at it more tonight after work. -- You received this bug notification because you are a member of Ubuntu Touch seeded packages, which is subscribed to sudo in Ubuntu. https://bugs.launchpad.net/bugs/1219337 Title: Users can change the clock without authenticating, allowing them to locally exploit sudo. Status in GNOME Control Center: Unknown Status in sudo: Unknown Status in Unity: Invalid Status in policykit-desktop-privileges package in Ubuntu: Opinion Status in sudo package in Ubuntu: Triaged Status in policykit-desktop-privileges source package in Precise: Opinion Status in sudo source package in Precise: Triaged Status in policykit-desktop-privileges source package in Trusty: Opinion Status in sudo source package in Trusty: Triaged Status in policykit-desktop-privileges source package in Utopic: Opinion Status in sudo source package in Utopic: Triaged Status in policykit-desktop-privileges source package in Vivid: Opinion Status in sudo source package in Vivid: Triaged Bug description: Under unity and cinnamon, it is possible for a user to turn off network-syncronized time and then change the time on the system. It is also possible to "cat /var/log/auth.log" and find the last time a user authenticated with sudo, along with which pty they used. If a user had used a terminal and successfully authenticated with sudo anytime in the past, and left the sudo file in "/var/lib/sudo//", a malicious user could walk up to an unlocked, logged in machine and gain sudo without knowing the password for the computer. To do this, a user would only need to launch a few terminals, figure out which pty they were on via "tty", find the an instance in /var/log/auth.log where sudo was used on that PTY, and set the clock to that time. Once this is done, they can run (for example) "sudo -s" and have a full access terminal. 1) This has been observed on Ubuntu 13.04, and may work on other versions. 2) This may have an effect on various window managers, but I confirmed it on Unity and Cinnamon 3) I expected to have to authenticate when I changed the time and date, as I do on Gnome and KDE. I also expected to be denied permission to auth.log 4) I was able to change the system time to whatever I wanted, and view auth.log. This was sufficient to access sudo without having to type my password. Note: This bug also affects any version of OS X, though the mechanism is different. Some versions don't require you to authenticate to change the time through the GUI, but some do. No version I've seen requires authentication to use the "systemsetup" command, which can alter the time from the command line. This may be an overall bug in sudo. Why can I bypass security by changing the time?! To manage notifications about this bug go to: https://bugs.launchpad.net/gnome-control-center/+bug/1219337/+subscriptions -- Mailing list: https://launchpad.net/~touch-packages Post to : touch-packages@lists.launchpad.net Unsubscribe : https://launchpad.net/~touch-packages More help : https://help.launchpad.net/ListHelp
[Touch-packages] [Bug 1219337] Re: Users can change the clock without authenticating, allowing them to locally exploit sudo.
So it's simply a matter of opening a bunch of terminals to get the same tty and rolling the sid in each of them. -- You received this bug notification because you are a member of Ubuntu Touch seeded packages, which is subscribed to sudo in Ubuntu. https://bugs.launchpad.net/bugs/1219337 Title: Users can change the clock without authenticating, allowing them to locally exploit sudo. Status in GNOME Control Center: Unknown Status in sudo: Unknown Status in Unity: Invalid Status in policykit-desktop-privileges package in Ubuntu: Opinion Status in sudo package in Ubuntu: Triaged Status in policykit-desktop-privileges source package in Precise: Opinion Status in sudo source package in Precise: Triaged Status in policykit-desktop-privileges source package in Trusty: Opinion Status in sudo source package in Trusty: Triaged Status in policykit-desktop-privileges source package in Utopic: Opinion Status in sudo source package in Utopic: Triaged Status in policykit-desktop-privileges source package in Vivid: Opinion Status in sudo source package in Vivid: Triaged Bug description: Under unity and cinnamon, it is possible for a user to turn off network-syncronized time and then change the time on the system. It is also possible to "cat /var/log/auth.log" and find the last time a user authenticated with sudo, along with which pty they used. If a user had used a terminal and successfully authenticated with sudo anytime in the past, and left the sudo file in "/var/lib/sudo//", a malicious user could walk up to an unlocked, logged in machine and gain sudo without knowing the password for the computer. To do this, a user would only need to launch a few terminals, figure out which pty they were on via "tty", find the an instance in /var/log/auth.log where sudo was used on that PTY, and set the clock to that time. Once this is done, they can run (for example) "sudo -s" and have a full access terminal. 1) This has been observed on Ubuntu 13.04, and may work on other versions. 2) This may have an effect on various window managers, but I confirmed it on Unity and Cinnamon 3) I expected to have to authenticate when I changed the time and date, as I do on Gnome and KDE. I also expected to be denied permission to auth.log 4) I was able to change the system time to whatever I wanted, and view auth.log. This was sufficient to access sudo without having to type my password. Note: This bug also affects any version of OS X, though the mechanism is different. Some versions don't require you to authenticate to change the time through the GUI, but some do. No version I've seen requires authentication to use the "systemsetup" command, which can alter the time from the command line. This may be an overall bug in sudo. Why can I bypass security by changing the time?! To manage notifications about this bug go to: https://bugs.launchpad.net/gnome-control-center/+bug/1219337/+subscriptions -- Mailing list: https://launchpad.net/~touch-packages Post to : touch-packages@lists.launchpad.net Unsubscribe : https://launchpad.net/~touch-packages More help : https://help.launchpad.net/ListHelp
[Touch-packages] [Bug 1219337] Re: Users can change the clock without authenticating, allowing them to locally exploit sudo.
Yes, there's a chance the same tty can get reused with the same inode if nothing else requires a tty in the meantime. -- You received this bug notification because you are a member of Ubuntu Touch seeded packages, which is subscribed to sudo in Ubuntu. https://bugs.launchpad.net/bugs/1219337 Title: Users can change the clock without authenticating, allowing them to locally exploit sudo. Status in GNOME Control Center: Unknown Status in sudo: Unknown Status in Unity: Invalid Status in policykit-desktop-privileges package in Ubuntu: Opinion Status in sudo package in Ubuntu: Triaged Status in policykit-desktop-privileges source package in Precise: Opinion Status in sudo source package in Precise: Triaged Status in policykit-desktop-privileges source package in Trusty: Opinion Status in sudo source package in Trusty: Triaged Status in policykit-desktop-privileges source package in Utopic: Opinion Status in sudo source package in Utopic: Triaged Status in policykit-desktop-privileges source package in Vivid: Opinion Status in sudo source package in Vivid: Triaged Bug description: Under unity and cinnamon, it is possible for a user to turn off network-syncronized time and then change the time on the system. It is also possible to "cat /var/log/auth.log" and find the last time a user authenticated with sudo, along with which pty they used. If a user had used a terminal and successfully authenticated with sudo anytime in the past, and left the sudo file in "/var/lib/sudo//", a malicious user could walk up to an unlocked, logged in machine and gain sudo without knowing the password for the computer. To do this, a user would only need to launch a few terminals, figure out which pty they were on via "tty", find the an instance in /var/log/auth.log where sudo was used on that PTY, and set the clock to that time. Once this is done, they can run (for example) "sudo -s" and have a full access terminal. 1) This has been observed on Ubuntu 13.04, and may work on other versions. 2) This may have an effect on various window managers, but I confirmed it on Unity and Cinnamon 3) I expected to have to authenticate when I changed the time and date, as I do on Gnome and KDE. I also expected to be denied permission to auth.log 4) I was able to change the system time to whatever I wanted, and view auth.log. This was sufficient to access sudo without having to type my password. Note: This bug also affects any version of OS X, though the mechanism is different. Some versions don't require you to authenticate to change the time through the GUI, but some do. No version I've seen requires authentication to use the "systemsetup" command, which can alter the time from the command line. This may be an overall bug in sudo. Why can I bypass security by changing the time?! To manage notifications about this bug go to: https://bugs.launchpad.net/gnome-control-center/+bug/1219337/+subscriptions -- Mailing list: https://launchpad.net/~touch-packages Post to : touch-packages@lists.launchpad.net Unsubscribe : https://launchpad.net/~touch-packages More help : https://help.launchpad.net/ListHelp
[Touch-packages] [Bug 1219337] Re: Users can change the clock without authenticating, allowing them to locally exploit sudo.
> Without rebooting, the tty, inode, sid should change for every terminal you open. When I tried this on 15.04, the tty and inode didnt: only the SID changed. Closing a gnome-terminal and reopening it got the same tty and SID. For *additional* terminals, they got new ttys and inodes, but if you close the one on /dev/pty/0 the file will dissapear. The next gnome- terminal you launch will be on /dev/pty/0 with the same inode as the old one you closed. Can you confirm? Apologies for any typos, I'm on my phone. -- You received this bug notification because you are a member of Ubuntu Touch seeded packages, which is subscribed to sudo in Ubuntu. https://bugs.launchpad.net/bugs/1219337 Title: Users can change the clock without authenticating, allowing them to locally exploit sudo. Status in GNOME Control Center: Unknown Status in sudo: Unknown Status in Unity: Invalid Status in policykit-desktop-privileges package in Ubuntu: Opinion Status in sudo package in Ubuntu: Triaged Status in policykit-desktop-privileges source package in Precise: Opinion Status in sudo source package in Precise: Triaged Status in policykit-desktop-privileges source package in Trusty: Opinion Status in sudo source package in Trusty: Triaged Status in policykit-desktop-privileges source package in Utopic: Opinion Status in sudo source package in Utopic: Triaged Status in policykit-desktop-privileges source package in Vivid: Opinion Status in sudo source package in Vivid: Triaged Bug description: Under unity and cinnamon, it is possible for a user to turn off network-syncronized time and then change the time on the system. It is also possible to "cat /var/log/auth.log" and find the last time a user authenticated with sudo, along with which pty they used. If a user had used a terminal and successfully authenticated with sudo anytime in the past, and left the sudo file in "/var/lib/sudo//", a malicious user could walk up to an unlocked, logged in machine and gain sudo without knowing the password for the computer. To do this, a user would only need to launch a few terminals, figure out which pty they were on via "tty", find the an instance in /var/log/auth.log where sudo was used on that PTY, and set the clock to that time. Once this is done, they can run (for example) "sudo -s" and have a full access terminal. 1) This has been observed on Ubuntu 13.04, and may work on other versions. 2) This may have an effect on various window managers, but I confirmed it on Unity and Cinnamon 3) I expected to have to authenticate when I changed the time and date, as I do on Gnome and KDE. I also expected to be denied permission to auth.log 4) I was able to change the system time to whatever I wanted, and view auth.log. This was sufficient to access sudo without having to type my password. Note: This bug also affects any version of OS X, though the mechanism is different. Some versions don't require you to authenticate to change the time through the GUI, but some do. No version I've seen requires authentication to use the "systemsetup" command, which can alter the time from the command line. This may be an overall bug in sudo. Why can I bypass security by changing the time?! To manage notifications about this bug go to: https://bugs.launchpad.net/gnome-control-center/+bug/1219337/+subscriptions -- Mailing list: https://launchpad.net/~touch-packages Post to : touch-packages@lists.launchpad.net Unsubscribe : https://launchpad.net/~touch-packages More help : https://help.launchpad.net/ListHelp
[Touch-packages] [Bug 1219337] Re: Users can change the clock without authenticating, allowing them to locally exploit sudo.
You could probably write a script that attempts to brute force low-digit sids and inodes when you supply a tty number. That should be possible. -- You received this bug notification because you are a member of Ubuntu Touch seeded packages, which is subscribed to sudo in Ubuntu. https://bugs.launchpad.net/bugs/1219337 Title: Users can change the clock without authenticating, allowing them to locally exploit sudo. Status in GNOME Control Center: Unknown Status in sudo: Unknown Status in Unity: Invalid Status in policykit-desktop-privileges package in Ubuntu: Opinion Status in sudo package in Ubuntu: Triaged Status in policykit-desktop-privileges source package in Precise: Opinion Status in sudo source package in Precise: Triaged Status in policykit-desktop-privileges source package in Trusty: Opinion Status in sudo source package in Trusty: Triaged Status in policykit-desktop-privileges source package in Utopic: Opinion Status in sudo source package in Utopic: Triaged Status in policykit-desktop-privileges source package in Vivid: Opinion Status in sudo source package in Vivid: Triaged Bug description: Under unity and cinnamon, it is possible for a user to turn off network-syncronized time and then change the time on the system. It is also possible to "cat /var/log/auth.log" and find the last time a user authenticated with sudo, along with which pty they used. If a user had used a terminal and successfully authenticated with sudo anytime in the past, and left the sudo file in "/var/lib/sudo//", a malicious user could walk up to an unlocked, logged in machine and gain sudo without knowing the password for the computer. To do this, a user would only need to launch a few terminals, figure out which pty they were on via "tty", find the an instance in /var/log/auth.log where sudo was used on that PTY, and set the clock to that time. Once this is done, they can run (for example) "sudo -s" and have a full access terminal. 1) This has been observed on Ubuntu 13.04, and may work on other versions. 2) This may have an effect on various window managers, but I confirmed it on Unity and Cinnamon 3) I expected to have to authenticate when I changed the time and date, as I do on Gnome and KDE. I also expected to be denied permission to auth.log 4) I was able to change the system time to whatever I wanted, and view auth.log. This was sufficient to access sudo without having to type my password. Note: This bug also affects any version of OS X, though the mechanism is different. Some versions don't require you to authenticate to change the time through the GUI, but some do. No version I've seen requires authentication to use the "systemsetup" command, which can alter the time from the command line. This may be an overall bug in sudo. Why can I bypass security by changing the time?! To manage notifications about this bug go to: https://bugs.launchpad.net/gnome-control-center/+bug/1219337/+subscriptions -- Mailing list: https://launchpad.net/~touch-packages Post to : touch-packages@lists.launchpad.net Unsubscribe : https://launchpad.net/~touch-packages More help : https://help.launchpad.net/ListHelp
[Touch-packages] [Bug 1219337] Re: Users can change the clock without authenticating, allowing them to locally exploit sudo.
Yes, the tty numbers and inodes reset when you reboot. That is why sudo has an init script that forcibly expires all the timestamp files when you reboot. Without rebooting, the tty, inode, sid should change for every terminal you open. -- You received this bug notification because you are a member of Ubuntu Touch seeded packages, which is subscribed to sudo in Ubuntu. https://bugs.launchpad.net/bugs/1219337 Title: Users can change the clock without authenticating, allowing them to locally exploit sudo. Status in GNOME Control Center: Unknown Status in sudo: Unknown Status in Unity: Invalid Status in policykit-desktop-privileges package in Ubuntu: Opinion Status in sudo package in Ubuntu: Triaged Status in policykit-desktop-privileges source package in Precise: Opinion Status in sudo source package in Precise: Triaged Status in policykit-desktop-privileges source package in Trusty: Opinion Status in sudo source package in Trusty: Triaged Status in policykit-desktop-privileges source package in Utopic: Opinion Status in sudo source package in Utopic: Triaged Status in policykit-desktop-privileges source package in Vivid: Opinion Status in sudo source package in Vivid: Triaged Bug description: Under unity and cinnamon, it is possible for a user to turn off network-syncronized time and then change the time on the system. It is also possible to "cat /var/log/auth.log" and find the last time a user authenticated with sudo, along with which pty they used. If a user had used a terminal and successfully authenticated with sudo anytime in the past, and left the sudo file in "/var/lib/sudo//", a malicious user could walk up to an unlocked, logged in machine and gain sudo without knowing the password for the computer. To do this, a user would only need to launch a few terminals, figure out which pty they were on via "tty", find the an instance in /var/log/auth.log where sudo was used on that PTY, and set the clock to that time. Once this is done, they can run (for example) "sudo -s" and have a full access terminal. 1) This has been observed on Ubuntu 13.04, and may work on other versions. 2) This may have an effect on various window managers, but I confirmed it on Unity and Cinnamon 3) I expected to have to authenticate when I changed the time and date, as I do on Gnome and KDE. I also expected to be denied permission to auth.log 4) I was able to change the system time to whatever I wanted, and view auth.log. This was sufficient to access sudo without having to type my password. Note: This bug also affects any version of OS X, though the mechanism is different. Some versions don't require you to authenticate to change the time through the GUI, but some do. No version I've seen requires authentication to use the "systemsetup" command, which can alter the time from the command line. This may be an overall bug in sudo. Why can I bypass security by changing the time?! To manage notifications about this bug go to: https://bugs.launchpad.net/gnome-control-center/+bug/1219337/+subscriptions -- Mailing list: https://launchpad.net/~touch-packages Post to : touch-packages@lists.launchpad.net Unsubscribe : https://launchpad.net/~touch-packages More help : https://help.launchpad.net/ListHelp
[Touch-packages] [Bug 1219337] Re: Users can change the clock without authenticating, allowing them to locally exploit sudo.
To clarify: I reboot, log in, open gnome-terminal. The tty is always /dev/pts/0, and ls -i /dev/pts/0 shows an inode of 3. This occurs even if I shut down and power back on, though admittedly in a VM. -- You received this bug notification because you are a member of Ubuntu Touch seeded packages, which is subscribed to sudo in Ubuntu. https://bugs.launchpad.net/bugs/1219337 Title: Users can change the clock without authenticating, allowing them to locally exploit sudo. Status in GNOME Control Center: Unknown Status in sudo: Unknown Status in Unity: Invalid Status in policykit-desktop-privileges package in Ubuntu: Opinion Status in sudo package in Ubuntu: Triaged Status in policykit-desktop-privileges source package in Precise: Opinion Status in sudo source package in Precise: Triaged Status in policykit-desktop-privileges source package in Trusty: Opinion Status in sudo source package in Trusty: Triaged Status in policykit-desktop-privileges source package in Utopic: Opinion Status in sudo source package in Utopic: Triaged Status in policykit-desktop-privileges source package in Vivid: Opinion Status in sudo source package in Vivid: Triaged Bug description: Under unity and cinnamon, it is possible for a user to turn off network-syncronized time and then change the time on the system. It is also possible to "cat /var/log/auth.log" and find the last time a user authenticated with sudo, along with which pty they used. If a user had used a terminal and successfully authenticated with sudo anytime in the past, and left the sudo file in "/var/lib/sudo//", a malicious user could walk up to an unlocked, logged in machine and gain sudo without knowing the password for the computer. To do this, a user would only need to launch a few terminals, figure out which pty they were on via "tty", find the an instance in /var/log/auth.log where sudo was used on that PTY, and set the clock to that time. Once this is done, they can run (for example) "sudo -s" and have a full access terminal. 1) This has been observed on Ubuntu 13.04, and may work on other versions. 2) This may have an effect on various window managers, but I confirmed it on Unity and Cinnamon 3) I expected to have to authenticate when I changed the time and date, as I do on Gnome and KDE. I also expected to be denied permission to auth.log 4) I was able to change the system time to whatever I wanted, and view auth.log. This was sufficient to access sudo without having to type my password. Note: This bug also affects any version of OS X, though the mechanism is different. Some versions don't require you to authenticate to change the time through the GUI, but some do. No version I've seen requires authentication to use the "systemsetup" command, which can alter the time from the command line. This may be an overall bug in sudo. Why can I bypass security by changing the time?! To manage notifications about this bug go to: https://bugs.launchpad.net/gnome-control-center/+bug/1219337/+subscriptions -- Mailing list: https://launchpad.net/~touch-packages Post to : touch-packages@lists.launchpad.net Unsubscribe : https://launchpad.net/~touch-packages More help : https://help.launchpad.net/ListHelp
[Touch-packages] [Bug 1219337] Re: Users can change the clock without authenticating, allowing them to locally exploit sudo.
Notice that only the SID changed though. That gives me a 1 in 32k chance, and I can generate them basically at will with setsid. In my testing so far, the inode of the TTY file for /dev/pts/0 has stayed "3" across several reboots. If it doesn't change, then it is moot from a security standpoint. -- You received this bug notification because you are a member of Ubuntu Touch seeded packages, which is subscribed to sudo in Ubuntu. https://bugs.launchpad.net/bugs/1219337 Title: Users can change the clock without authenticating, allowing them to locally exploit sudo. Status in GNOME Control Center: Unknown Status in sudo: Unknown Status in Unity: Invalid Status in policykit-desktop-privileges package in Ubuntu: Opinion Status in sudo package in Ubuntu: Triaged Status in policykit-desktop-privileges source package in Precise: Opinion Status in sudo source package in Precise: Triaged Status in policykit-desktop-privileges source package in Trusty: Opinion Status in sudo source package in Trusty: Triaged Status in policykit-desktop-privileges source package in Utopic: Opinion Status in sudo source package in Utopic: Triaged Status in policykit-desktop-privileges source package in Vivid: Opinion Status in sudo source package in Vivid: Triaged Bug description: Under unity and cinnamon, it is possible for a user to turn off network-syncronized time and then change the time on the system. It is also possible to "cat /var/log/auth.log" and find the last time a user authenticated with sudo, along with which pty they used. If a user had used a terminal and successfully authenticated with sudo anytime in the past, and left the sudo file in "/var/lib/sudo//", a malicious user could walk up to an unlocked, logged in machine and gain sudo without knowing the password for the computer. To do this, a user would only need to launch a few terminals, figure out which pty they were on via "tty", find the an instance in /var/log/auth.log where sudo was used on that PTY, and set the clock to that time. Once this is done, they can run (for example) "sudo -s" and have a full access terminal. 1) This has been observed on Ubuntu 13.04, and may work on other versions. 2) This may have an effect on various window managers, but I confirmed it on Unity and Cinnamon 3) I expected to have to authenticate when I changed the time and date, as I do on Gnome and KDE. I also expected to be denied permission to auth.log 4) I was able to change the system time to whatever I wanted, and view auth.log. This was sufficient to access sudo without having to type my password. Note: This bug also affects any version of OS X, though the mechanism is different. Some versions don't require you to authenticate to change the time through the GUI, but some do. No version I've seen requires authentication to use the "systemsetup" command, which can alter the time from the command line. This may be an overall bug in sudo. Why can I bypass security by changing the time?! To manage notifications about this bug go to: https://bugs.launchpad.net/gnome-control-center/+bug/1219337/+subscriptions -- Mailing list: https://launchpad.net/~touch-packages Post to : touch-packages@lists.launchpad.net Unsubscribe : https://launchpad.net/~touch-packages More help : https://help.launchpad.net/ListHelp
[Touch-packages] [Bug 1219337] Re: Users can change the clock without authenticating, allowing them to locally exploit sudo.
Hi Mark, In your first hexdump, this is what those values represent: 00013 = id of the device the tty is on 34816 = device id of the tty file 3 = inode of the tty file 01000 = uid of the tty file 5 = gid of the tty file 31291 = sid The id of the device the tty is on is known. So is the uid and gid. The device id of the tty file can be found in auth.log. So that leaves the inode of the tty file and the sid. You need to be able to open a new tty and hit the same tty number, the same sid and the same inode, and you need to do it blindly without knowing in advance what the inode and the sid were. -- You received this bug notification because you are a member of Ubuntu Touch seeded packages, which is subscribed to sudo in Ubuntu. https://bugs.launchpad.net/bugs/1219337 Title: Users can change the clock without authenticating, allowing them to locally exploit sudo. Status in GNOME Control Center: Unknown Status in sudo: Unknown Status in Unity: Invalid Status in policykit-desktop-privileges package in Ubuntu: Opinion Status in sudo package in Ubuntu: Triaged Status in policykit-desktop-privileges source package in Precise: Opinion Status in sudo source package in Precise: Triaged Status in policykit-desktop-privileges source package in Trusty: Opinion Status in sudo source package in Trusty: Triaged Status in policykit-desktop-privileges source package in Utopic: Opinion Status in sudo source package in Utopic: Triaged Status in policykit-desktop-privileges source package in Vivid: Opinion Status in sudo source package in Vivid: Triaged Bug description: Under unity and cinnamon, it is possible for a user to turn off network-syncronized time and then change the time on the system. It is also possible to "cat /var/log/auth.log" and find the last time a user authenticated with sudo, along with which pty they used. If a user had used a terminal and successfully authenticated with sudo anytime in the past, and left the sudo file in "/var/lib/sudo//", a malicious user could walk up to an unlocked, logged in machine and gain sudo without knowing the password for the computer. To do this, a user would only need to launch a few terminals, figure out which pty they were on via "tty", find the an instance in /var/log/auth.log where sudo was used on that PTY, and set the clock to that time. Once this is done, they can run (for example) "sudo -s" and have a full access terminal. 1) This has been observed on Ubuntu 13.04, and may work on other versions. 2) This may have an effect on various window managers, but I confirmed it on Unity and Cinnamon 3) I expected to have to authenticate when I changed the time and date, as I do on Gnome and KDE. I also expected to be denied permission to auth.log 4) I was able to change the system time to whatever I wanted, and view auth.log. This was sufficient to access sudo without having to type my password. Note: This bug also affects any version of OS X, though the mechanism is different. Some versions don't require you to authenticate to change the time through the GUI, but some do. No version I've seen requires authentication to use the "systemsetup" command, which can alter the time from the command line. This may be an overall bug in sudo. Why can I bypass security by changing the time?! To manage notifications about this bug go to: https://bugs.launchpad.net/gnome-control-center/+bug/1219337/+subscriptions -- Mailing list: https://launchpad.net/~touch-packages Post to : touch-packages@lists.launchpad.net Unsubscribe : https://launchpad.net/~touch-packages More help : https://help.launchpad.net/ListHelp
[Touch-packages] [Bug 1219337] Re: Users can change the clock without authenticating, allowing them to locally exploit sudo.
Tyler, it's great that this bug will be fixed. However, I have some concerns about the mitigations factors. 1) Timestamp: Easily found in the auth.log, and easily bypassed due to an unlocked clock. 2) TTY: The tty of the first gnome-terminal running is (as far as I can tell) /dev/pts/0. That's predictable, so if the auth.log contains a sudo session on /dev/pty/0, it's trivial to re-create the tty. 3) inode: Does this mean Session ID? If so, I'm worried. If not, we have a bigger problem. Here's why: hexdump -d /var/lib/sudo/mscs/0 000 00013 0 0 0 34816 0 0 0 010 3 0 0 0 01000 0 5 0 020 31291 0 0 0 028 hexdump -d /var/lib/sudo/mscs/0 000 00013 0 0 0 34816 0 0 0 010 3 0 0 0 01000 0 5 0 020 01464 0 0 0 028 See 31291, and 01464 in the second column near the bottom? It turns out that they correspond to SID. I checked using python: import os pid = os.getpid() sid = os.getsid(pid) print pid, sid 1775 1464 I tested this several times. Since the setsid can generate a new sid, and there are only 32768 possible SIDs as configured out of the box, how hard would it be to brute force the sid, simply running sudo -n -s? If SID isn't == to Inode, where's inode in that file? The ls -i command reports no difference in the inode of the file itself (545179 both times, even if the gnome-terminal is closed and re-opened.) I've poked at the sid option already, and have indeed had good success with getting sessions matching the sid using this brute force method. It's now a question of how I get that session lined up with the pty (which is predictable) and see if sudo -s works without a password at the last escalation time. Perhaps there is some other security feature that will block me, but right now I don't see it. Thoughts? -- You received this bug notification because you are a member of Ubuntu Touch seeded packages, which is subscribed to sudo in Ubuntu. https://bugs.launchpad.net/bugs/1219337 Title: Users can change the clock without authenticating, allowing them to locally exploit sudo. Status in GNOME Control Center: Unknown Status in sudo: Unknown Status in Unity: Invalid Status in policykit-desktop-privileges package in Ubuntu: Opinion Status in sudo package in Ubuntu: Triaged Status in policykit-desktop-privileges source package in Precise: Opinion Status in sudo source package in Precise: Triaged Status in policykit-desktop-privileges source package in Trusty: Opinion Status in sudo source package in Trusty: Triaged Status in policykit-desktop-privileges source package in Utopic: Opinion Status in sudo source package in Utopic: Triaged Status in policykit-desktop-privileges source package in Vivid: Opinion Status in sudo source package in Vivid: Triaged Bug description: Under unity and cinnamon, it is possible for a user to turn off network-syncronized time and then change the time on the system. It is also possible to "cat /var/log/auth.log" and find the last time a user authenticated with sudo, along with which pty they used. If a user had used a terminal and successfully authenticated with sudo anytime in the past, and left the sudo file in "/var/lib/sudo//", a malicious user could walk up to an unlocked, logged in machine and gain sudo without knowing the password for the computer. To do this, a user would only need to launch a few terminals, figure out which pty they were on via "tty", find the an instance in /var/log/auth.log where sudo was used on that PTY, and set the clock to that time. Once this is done, they can run (for example) "sudo -s" and have a full access terminal. 1) This has been observed on Ubuntu 13.04, and may work on other versions. 2) This may have an effect on various window managers, but I confirmed it on Unity and Cinnamon 3) I expected to have to authenticate when I changed the time and date, as I do on Gnome and KDE. I also expected to be denied permission to auth.log 4) I was able to change the system time to whatever I wanted, and view auth.log. This was sufficient to access sudo without having to type my password. Note: This bug also affects any version of OS X, though the mechanism is different. Some versions don't require you to authenticate to change the time through the GUI, but some do. No version I've seen requires authentication to use the "systemsetup" command, which can alter the time from the command line. This may be an overall bug in sudo. Why can I bypass security by changing the time?! To manage notifications about this bug go to: https://bugs.launchpad.net/gnome-control-center/+bug/1219337/+subscriptions -- Mailing list: https://launchpad.net/~touch-packages Post to
[Touch-packages] [Bug 1219337] Re: Users can change the clock without authenticating, allowing them to locally exploit sudo.
** Also affects: gnome-control-center via https://bugzilla.gnome.org/show_bug.cgi?id=646185 Importance: Unknown Status: Unknown ** No longer affects: gnome-control-center ** Bug watch added: GNOME Bug Tracker #646185 https://bugzilla.gnome.org/show_bug.cgi?id=646185 ** Project changed: cinnamon-desktop => gnome-control-center ** Changed in: gnome-control-center Importance: Undecided => Unknown ** Changed in: gnome-control-center Status: New => Unknown ** Changed in: gnome-control-center Remote watch: None => GNOME Bug Tracker #646185 -- You received this bug notification because you are a member of Ubuntu Touch seeded packages, which is subscribed to policykit-desktop- privileges in Ubuntu. https://bugs.launchpad.net/bugs/1219337 Title: Users can change the clock without authenticating, allowing them to locally exploit sudo. Status in GNOME Control Center: Unknown Status in sudo: Unknown Status in Unity: Invalid Status in policykit-desktop-privileges package in Ubuntu: Opinion Status in sudo package in Ubuntu: Triaged Status in policykit-desktop-privileges source package in Precise: Opinion Status in sudo source package in Precise: Triaged Status in policykit-desktop-privileges source package in Trusty: Opinion Status in sudo source package in Trusty: Triaged Status in policykit-desktop-privileges source package in Utopic: Opinion Status in sudo source package in Utopic: Triaged Status in policykit-desktop-privileges source package in Vivid: Opinion Status in sudo source package in Vivid: Triaged Bug description: Under unity and cinnamon, it is possible for a user to turn off network-syncronized time and then change the time on the system. It is also possible to "cat /var/log/auth.log" and find the last time a user authenticated with sudo, along with which pty they used. If a user had used a terminal and successfully authenticated with sudo anytime in the past, and left the sudo file in "/var/lib/sudo//", a malicious user could walk up to an unlocked, logged in machine and gain sudo without knowing the password for the computer. To do this, a user would only need to launch a few terminals, figure out which pty they were on via "tty", find the an instance in /var/log/auth.log where sudo was used on that PTY, and set the clock to that time. Once this is done, they can run (for example) "sudo -s" and have a full access terminal. 1) This has been observed on Ubuntu 13.04, and may work on other versions. 2) This may have an effect on various window managers, but I confirmed it on Unity and Cinnamon 3) I expected to have to authenticate when I changed the time and date, as I do on Gnome and KDE. I also expected to be denied permission to auth.log 4) I was able to change the system time to whatever I wanted, and view auth.log. This was sufficient to access sudo without having to type my password. Note: This bug also affects any version of OS X, though the mechanism is different. Some versions don't require you to authenticate to change the time through the GUI, but some do. No version I've seen requires authentication to use the "systemsetup" command, which can alter the time from the command line. This may be an overall bug in sudo. Why can I bypass security by changing the time?! To manage notifications about this bug go to: https://bugs.launchpad.net/gnome-control-center/+bug/1219337/+subscriptions -- Mailing list: https://launchpad.net/~touch-packages Post to : touch-packages@lists.launchpad.net Unsubscribe : https://launchpad.net/~touch-packages More help : https://help.launchpad.net/ListHelp
[Touch-packages] [Bug 1219337] Re: Users can change the clock without authenticating, allowing them to locally exploit sudo.
** Changed in: sudo (Ubuntu Precise) Status: Confirmed => Triaged ** Changed in: sudo (Ubuntu Precise) Importance: Undecided => Low ** Changed in: sudo (Ubuntu Trusty) Status: Confirmed => Triaged ** Changed in: sudo (Ubuntu Trusty) Importance: Undecided => Low ** Changed in: sudo (Ubuntu Utopic) Status: Confirmed => Triaged ** Changed in: sudo (Ubuntu Utopic) Importance: Undecided => Low ** Changed in: sudo (Ubuntu Vivid) Status: Confirmed => Triaged ** Changed in: sudo (Ubuntu Vivid) Importance: Undecided => Low ** Changed in: sudo (Ubuntu Precise) Assignee: Marc Deslauriers (mdeslaur) => (unassigned) ** Changed in: sudo (Ubuntu Trusty) Assignee: Marc Deslauriers (mdeslaur) => (unassigned) ** Changed in: sudo (Ubuntu Utopic) Assignee: Marc Deslauriers (mdeslaur) => (unassigned) ** Changed in: sudo (Ubuntu Vivid) Assignee: Marc Deslauriers (mdeslaur) => (unassigned) -- You received this bug notification because you are a member of Ubuntu Touch seeded packages, which is subscribed to sudo in Ubuntu. https://bugs.launchpad.net/bugs/1219337 Title: Users can change the clock without authenticating, allowing them to locally exploit sudo. Status in Cinnamon: New Status in sudo: Unknown Status in Unity: Invalid Status in policykit-desktop-privileges package in Ubuntu: Opinion Status in sudo package in Ubuntu: Triaged Status in policykit-desktop-privileges source package in Precise: Opinion Status in sudo source package in Precise: Triaged Status in policykit-desktop-privileges source package in Trusty: Opinion Status in sudo source package in Trusty: Triaged Status in policykit-desktop-privileges source package in Utopic: Opinion Status in sudo source package in Utopic: Triaged Status in policykit-desktop-privileges source package in Vivid: Opinion Status in sudo source package in Vivid: Triaged Bug description: Under unity and cinnamon, it is possible for a user to turn off network-syncronized time and then change the time on the system. It is also possible to "cat /var/log/auth.log" and find the last time a user authenticated with sudo, along with which pty they used. If a user had used a terminal and successfully authenticated with sudo anytime in the past, and left the sudo file in "/var/lib/sudo//", a malicious user could walk up to an unlocked, logged in machine and gain sudo without knowing the password for the computer. To do this, a user would only need to launch a few terminals, figure out which pty they were on via "tty", find the an instance in /var/log/auth.log where sudo was used on that PTY, and set the clock to that time. Once this is done, they can run (for example) "sudo -s" and have a full access terminal. 1) This has been observed on Ubuntu 13.04, and may work on other versions. 2) This may have an effect on various window managers, but I confirmed it on Unity and Cinnamon 3) I expected to have to authenticate when I changed the time and date, as I do on Gnome and KDE. I also expected to be denied permission to auth.log 4) I was able to change the system time to whatever I wanted, and view auth.log. This was sufficient to access sudo without having to type my password. Note: This bug also affects any version of OS X, though the mechanism is different. Some versions don't require you to authenticate to change the time through the GUI, but some do. No version I've seen requires authentication to use the "systemsetup" command, which can alter the time from the command line. This may be an overall bug in sudo. Why can I bypass security by changing the time?! To manage notifications about this bug go to: https://bugs.launchpad.net/cinnamon-desktop/+bug/1219337/+subscriptions -- Mailing list: https://launchpad.net/~touch-packages Post to : touch-packages@lists.launchpad.net Unsubscribe : https://launchpad.net/~touch-packages More help : https://help.launchpad.net/ListHelp
[Touch-packages] [Bug 1219337] Re: Users can change the clock without authenticating, allowing them to locally exploit sudo.
Hi Mark - I've taken a look at the details in this bug, the upstream sudo bug, the /r/linux thread, and the upstream sudo fix. I appreciate and respect your thoroughness. After taking all of the details into account, I consider this issue to be low severity due to the mitigating factors involved. Specifically, I don't see a way for an attacker, without physical access, to use an arbitrary code execution vulnerability in combination with the issue that you've described in this bug to elevate his/her privileges. Considering this, the attack requires an admin user leave his/her desktop session unlocked and for an attacker to come across this unlocked desktop session. Since there are many different ways to attack an unlocked desktop session, best security practices dictate all users lock their screens when not at their computer. We will fix this issue in the next Ubuntu release (15.10) by including sudo 1.8.10 or newer. Due to the issue’s low severity and considering our practice of prioritizing resources on publishing security updates that fix issues of greater security impact, we may fix this issue in stable releases of Ubuntu in the future if another sudo vulnerability of higher severity is found or if new details emerge regarding this issue. -- You received this bug notification because you are a member of Ubuntu Touch seeded packages, which is subscribed to sudo in Ubuntu. https://bugs.launchpad.net/bugs/1219337 Title: Users can change the clock without authenticating, allowing them to locally exploit sudo. Status in Cinnamon: New Status in sudo: Unknown Status in Unity: Invalid Status in policykit-desktop-privileges package in Ubuntu: Opinion Status in sudo package in Ubuntu: Confirmed Status in policykit-desktop-privileges source package in Precise: Opinion Status in sudo source package in Precise: Confirmed Status in policykit-desktop-privileges source package in Trusty: Opinion Status in sudo source package in Trusty: Confirmed Status in policykit-desktop-privileges source package in Utopic: Opinion Status in sudo source package in Utopic: Confirmed Status in policykit-desktop-privileges source package in Vivid: Opinion Status in sudo source package in Vivid: Confirmed Bug description: Under unity and cinnamon, it is possible for a user to turn off network-syncronized time and then change the time on the system. It is also possible to "cat /var/log/auth.log" and find the last time a user authenticated with sudo, along with which pty they used. If a user had used a terminal and successfully authenticated with sudo anytime in the past, and left the sudo file in "/var/lib/sudo//", a malicious user could walk up to an unlocked, logged in machine and gain sudo without knowing the password for the computer. To do this, a user would only need to launch a few terminals, figure out which pty they were on via "tty", find the an instance in /var/log/auth.log where sudo was used on that PTY, and set the clock to that time. Once this is done, they can run (for example) "sudo -s" and have a full access terminal. 1) This has been observed on Ubuntu 13.04, and may work on other versions. 2) This may have an effect on various window managers, but I confirmed it on Unity and Cinnamon 3) I expected to have to authenticate when I changed the time and date, as I do on Gnome and KDE. I also expected to be denied permission to auth.log 4) I was able to change the system time to whatever I wanted, and view auth.log. This was sufficient to access sudo without having to type my password. Note: This bug also affects any version of OS X, though the mechanism is different. Some versions don't require you to authenticate to change the time through the GUI, but some do. No version I've seen requires authentication to use the "systemsetup" command, which can alter the time from the command line. This may be an overall bug in sudo. Why can I bypass security by changing the time?! To manage notifications about this bug go to: https://bugs.launchpad.net/cinnamon-desktop/+bug/1219337/+subscriptions -- Mailing list: https://launchpad.net/~touch-packages Post to : touch-packages@lists.launchpad.net Unsubscribe : https://launchpad.net/~touch-packages More help : https://help.launchpad.net/ListHelp
[Touch-packages] [Bug 1219337] Re: Users can change the clock without authenticating, allowing them to locally exploit sudo.
> Debian hasn't fixed this in squeeze or wheezy yet, it's fixed in jessie because they have a recent enough version of sudo. They haven't fixed it because they were never vulnerable: they don't allow you to change the clock without a password. > We do plan on backporting monolithic timer support, we just have not had time yet. Was a year and two releases not enough time? -- You received this bug notification because you are a member of Ubuntu Touch seeded packages, which is subscribed to sudo in Ubuntu. https://bugs.launchpad.net/bugs/1219337 Title: Users can change the clock without authenticating, allowing them to locally exploit sudo. Status in Cinnamon: New Status in sudo: Unknown Status in Unity: Invalid Status in policykit-desktop-privileges package in Ubuntu: Opinion Status in sudo package in Ubuntu: Confirmed Status in policykit-desktop-privileges source package in Precise: Opinion Status in sudo source package in Precise: Confirmed Status in policykit-desktop-privileges source package in Trusty: Opinion Status in sudo source package in Trusty: Confirmed Status in policykit-desktop-privileges source package in Utopic: Opinion Status in sudo source package in Utopic: Confirmed Status in policykit-desktop-privileges source package in Vivid: Opinion Status in sudo source package in Vivid: Confirmed Bug description: Under unity and cinnamon, it is possible for a user to turn off network-syncronized time and then change the time on the system. It is also possible to "cat /var/log/auth.log" and find the last time a user authenticated with sudo, along with which pty they used. If a user had used a terminal and successfully authenticated with sudo anytime in the past, and left the sudo file in "/var/lib/sudo//", a malicious user could walk up to an unlocked, logged in machine and gain sudo without knowing the password for the computer. To do this, a user would only need to launch a few terminals, figure out which pty they were on via "tty", find the an instance in /var/log/auth.log where sudo was used on that PTY, and set the clock to that time. Once this is done, they can run (for example) "sudo -s" and have a full access terminal. 1) This has been observed on Ubuntu 13.04, and may work on other versions. 2) This may have an effect on various window managers, but I confirmed it on Unity and Cinnamon 3) I expected to have to authenticate when I changed the time and date, as I do on Gnome and KDE. I also expected to be denied permission to auth.log 4) I was able to change the system time to whatever I wanted, and view auth.log. This was sufficient to access sudo without having to type my password. Note: This bug also affects any version of OS X, though the mechanism is different. Some versions don't require you to authenticate to change the time through the GUI, but some do. No version I've seen requires authentication to use the "systemsetup" command, which can alter the time from the command line. This may be an overall bug in sudo. Why can I bypass security by changing the time?! To manage notifications about this bug go to: https://bugs.launchpad.net/cinnamon-desktop/+bug/1219337/+subscriptions -- Mailing list: https://launchpad.net/~touch-packages Post to : touch-packages@lists.launchpad.net Unsubscribe : https://launchpad.net/~touch-packages More help : https://help.launchpad.net/ListHelp
[Touch-packages] [Bug 1219337] Re: Users can change the clock without authenticating, allowing them to locally exploit sudo.
/* * Info stored in tty ticket from stat(2) to help with tty matching. */ static struct tty_info { dev_t dev; /* ID of device tty resides on */ dev_t rdev; /* tty device ID */ ino_t ino; /* tty inode number */ struct timeval ctime; /* tty inode change time */ } tty_info; That is the info required. Yes, if you leave your terminal open, the pty is still there. Debian hasn't fixed this in squeeze or wheezy yet, it's fixed in jessie because they have a recent enough version of sudo. We do plan on backporting monolithic timer support, we just have not had time yet. -- You received this bug notification because you are a member of Ubuntu Touch seeded packages, which is subscribed to sudo in Ubuntu. https://bugs.launchpad.net/bugs/1219337 Title: Users can change the clock without authenticating, allowing them to locally exploit sudo. Status in Cinnamon: New Status in sudo: Unknown Status in Unity: Invalid Status in policykit-desktop-privileges package in Ubuntu: Opinion Status in sudo package in Ubuntu: Confirmed Status in policykit-desktop-privileges source package in Precise: Opinion Status in sudo source package in Precise: Confirmed Status in policykit-desktop-privileges source package in Trusty: Opinion Status in sudo source package in Trusty: Confirmed Status in policykit-desktop-privileges source package in Utopic: Opinion Status in sudo source package in Utopic: Confirmed Status in policykit-desktop-privileges source package in Vivid: Opinion Status in sudo source package in Vivid: Confirmed Bug description: Under unity and cinnamon, it is possible for a user to turn off network-syncronized time and then change the time on the system. It is also possible to "cat /var/log/auth.log" and find the last time a user authenticated with sudo, along with which pty they used. If a user had used a terminal and successfully authenticated with sudo anytime in the past, and left the sudo file in "/var/lib/sudo//", a malicious user could walk up to an unlocked, logged in machine and gain sudo without knowing the password for the computer. To do this, a user would only need to launch a few terminals, figure out which pty they were on via "tty", find the an instance in /var/log/auth.log where sudo was used on that PTY, and set the clock to that time. Once this is done, they can run (for example) "sudo -s" and have a full access terminal. 1) This has been observed on Ubuntu 13.04, and may work on other versions. 2) This may have an effect on various window managers, but I confirmed it on Unity and Cinnamon 3) I expected to have to authenticate when I changed the time and date, as I do on Gnome and KDE. I also expected to be denied permission to auth.log 4) I was able to change the system time to whatever I wanted, and view auth.log. This was sufficient to access sudo without having to type my password. Note: This bug also affects any version of OS X, though the mechanism is different. Some versions don't require you to authenticate to change the time through the GUI, but some do. No version I've seen requires authentication to use the "systemsetup" command, which can alter the time from the command line. This may be an overall bug in sudo. Why can I bypass security by changing the time?! To manage notifications about this bug go to: https://bugs.launchpad.net/cinnamon-desktop/+bug/1219337/+subscriptions -- Mailing list: https://launchpad.net/~touch-packages Post to : touch-packages@lists.launchpad.net Unsubscribe : https://launchpad.net/~touch-packages More help : https://help.launchpad.net/ListHelp
[Touch-packages] [Bug 1219337] Re: Users can change the clock without authenticating, allowing them to locally exploit sudo.
Really? If the terminal I last ran sudo in is open still on the machine, and it's unlocked, I couldn't simply change the time back to the previous sudo command an escalate? Even if it's a remote chance, it's still an easy exploit. /var/log/auth.log is certainly readable by a program that uses a different exploit to gain access to that admin user (say, a browser exploit) and contains the PTY and timestamp. It doesn't even have to be exact: It just has to be ~ 15 minutes after the last sudo, right? This is a simple upgrade that even your parent distribution has adopted for their stable. Why ignore it for over a year? Can you please show me the information about the inode? My impression was that it was based on the SID, rather than inode, but perhaps that has changed. -- You received this bug notification because you are a member of Ubuntu Touch seeded packages, which is subscribed to sudo in Ubuntu. https://bugs.launchpad.net/bugs/1219337 Title: Users can change the clock without authenticating, allowing them to locally exploit sudo. Status in Cinnamon: New Status in sudo: Unknown Status in Unity: Invalid Status in policykit-desktop-privileges package in Ubuntu: Opinion Status in sudo package in Ubuntu: Confirmed Status in policykit-desktop-privileges source package in Precise: Opinion Status in sudo source package in Precise: Confirmed Status in policykit-desktop-privileges source package in Trusty: Opinion Status in sudo source package in Trusty: Confirmed Status in policykit-desktop-privileges source package in Utopic: Opinion Status in sudo source package in Utopic: Confirmed Status in policykit-desktop-privileges source package in Vivid: Opinion Status in sudo source package in Vivid: Confirmed Bug description: Under unity and cinnamon, it is possible for a user to turn off network-syncronized time and then change the time on the system. It is also possible to "cat /var/log/auth.log" and find the last time a user authenticated with sudo, along with which pty they used. If a user had used a terminal and successfully authenticated with sudo anytime in the past, and left the sudo file in "/var/lib/sudo//", a malicious user could walk up to an unlocked, logged in machine and gain sudo without knowing the password for the computer. To do this, a user would only need to launch a few terminals, figure out which pty they were on via "tty", find the an instance in /var/log/auth.log where sudo was used on that PTY, and set the clock to that time. Once this is done, they can run (for example) "sudo -s" and have a full access terminal. 1) This has been observed on Ubuntu 13.04, and may work on other versions. 2) This may have an effect on various window managers, but I confirmed it on Unity and Cinnamon 3) I expected to have to authenticate when I changed the time and date, as I do on Gnome and KDE. I also expected to be denied permission to auth.log 4) I was able to change the system time to whatever I wanted, and view auth.log. This was sufficient to access sudo without having to type my password. Note: This bug also affects any version of OS X, though the mechanism is different. Some versions don't require you to authenticate to change the time through the GUI, but some do. No version I've seen requires authentication to use the "systemsetup" command, which can alter the time from the command line. This may be an overall bug in sudo. Why can I bypass security by changing the time?! To manage notifications about this bug go to: https://bugs.launchpad.net/cinnamon-desktop/+bug/1219337/+subscriptions -- Mailing list: https://launchpad.net/~touch-packages Post to : touch-packages@lists.launchpad.net Unsubscribe : https://launchpad.net/~touch-packages More help : https://help.launchpad.net/ListHelp
[Touch-packages] [Bug 1219337] Re: Users can change the clock without authenticating, allowing them to locally exploit sudo.
** Also affects: sudo (Ubuntu Utopic) Importance: Undecided Status: New ** Also affects: policykit-desktop-privileges (Ubuntu Utopic) Importance: Undecided Status: New ** Also affects: sudo (Ubuntu Precise) Importance: Undecided Status: New ** Also affects: policykit-desktop-privileges (Ubuntu Precise) Importance: Undecided Status: New ** Also affects: sudo (Ubuntu Vivid) Importance: Undecided Status: Confirmed ** Also affects: policykit-desktop-privileges (Ubuntu Vivid) Importance: Undecided Status: Opinion ** Also affects: sudo (Ubuntu Trusty) Importance: Undecided Status: New ** Also affects: policykit-desktop-privileges (Ubuntu Trusty) Importance: Undecided Status: New ** Changed in: policykit-desktop-privileges (Ubuntu Precise) Status: New => Opinion ** Changed in: policykit-desktop-privileges (Ubuntu Trusty) Status: New => Opinion ** Changed in: policykit-desktop-privileges (Ubuntu Utopic) Status: New => Opinion ** Changed in: sudo (Ubuntu Precise) Status: New => Confirmed ** Changed in: sudo (Ubuntu Trusty) Status: New => Confirmed ** Changed in: sudo (Ubuntu Utopic) Status: New => Confirmed -- You received this bug notification because you are a member of Ubuntu Touch seeded packages, which is subscribed to sudo in Ubuntu. https://bugs.launchpad.net/bugs/1219337 Title: Users can change the clock without authenticating, allowing them to locally exploit sudo. Status in Cinnamon: New Status in sudo: Unknown Status in Unity: Invalid Status in policykit-desktop-privileges package in Ubuntu: Opinion Status in sudo package in Ubuntu: Confirmed Status in policykit-desktop-privileges source package in Precise: Opinion Status in sudo source package in Precise: Confirmed Status in policykit-desktop-privileges source package in Trusty: Opinion Status in sudo source package in Trusty: Confirmed Status in policykit-desktop-privileges source package in Utopic: Opinion Status in sudo source package in Utopic: Confirmed Status in policykit-desktop-privileges source package in Vivid: Opinion Status in sudo source package in Vivid: Confirmed Bug description: Under unity and cinnamon, it is possible for a user to turn off network-syncronized time and then change the time on the system. It is also possible to "cat /var/log/auth.log" and find the last time a user authenticated with sudo, along with which pty they used. If a user had used a terminal and successfully authenticated with sudo anytime in the past, and left the sudo file in "/var/lib/sudo//", a malicious user could walk up to an unlocked, logged in machine and gain sudo without knowing the password for the computer. To do this, a user would only need to launch a few terminals, figure out which pty they were on via "tty", find the an instance in /var/log/auth.log where sudo was used on that PTY, and set the clock to that time. Once this is done, they can run (for example) "sudo -s" and have a full access terminal. 1) This has been observed on Ubuntu 13.04, and may work on other versions. 2) This may have an effect on various window managers, but I confirmed it on Unity and Cinnamon 3) I expected to have to authenticate when I changed the time and date, as I do on Gnome and KDE. I also expected to be denied permission to auth.log 4) I was able to change the system time to whatever I wanted, and view auth.log. This was sufficient to access sudo without having to type my password. Note: This bug also affects any version of OS X, though the mechanism is different. Some versions don't require you to authenticate to change the time through the GUI, but some do. No version I've seen requires authentication to use the "systemsetup" command, which can alter the time from the command line. This may be an overall bug in sudo. Why can I bypass security by changing the time?! To manage notifications about this bug go to: https://bugs.launchpad.net/cinnamon-desktop/+bug/1219337/+subscriptions -- Mailing list: https://launchpad.net/~touch-packages Post to : touch-packages@lists.launchpad.net Unsubscribe : https://launchpad.net/~touch-packages More help : https://help.launchpad.net/ListHelp
[Touch-packages] [Bug 1219337] Re: Users can change the clock without authenticating, allowing them to locally exploit sudo.
** Changed in: sudo (Ubuntu Precise) Assignee: (unassigned) => Marc Deslauriers (mdeslaur) ** Changed in: sudo (Ubuntu Trusty) Assignee: (unassigned) => Marc Deslauriers (mdeslaur) ** Changed in: sudo (Ubuntu Utopic) Assignee: (unassigned) => Marc Deslauriers (mdeslaur) ** Changed in: sudo (Ubuntu Vivid) Assignee: (unassigned) => Marc Deslauriers (mdeslaur) -- You received this bug notification because you are a member of Ubuntu Touch seeded packages, which is subscribed to sudo in Ubuntu. https://bugs.launchpad.net/bugs/1219337 Title: Users can change the clock without authenticating, allowing them to locally exploit sudo. Status in Cinnamon: New Status in sudo: Unknown Status in Unity: Invalid Status in policykit-desktop-privileges package in Ubuntu: Opinion Status in sudo package in Ubuntu: Confirmed Status in policykit-desktop-privileges source package in Precise: Opinion Status in sudo source package in Precise: Confirmed Status in policykit-desktop-privileges source package in Trusty: Opinion Status in sudo source package in Trusty: Confirmed Status in policykit-desktop-privileges source package in Utopic: Opinion Status in sudo source package in Utopic: Confirmed Status in policykit-desktop-privileges source package in Vivid: Opinion Status in sudo source package in Vivid: Confirmed Bug description: Under unity and cinnamon, it is possible for a user to turn off network-syncronized time and then change the time on the system. It is also possible to "cat /var/log/auth.log" and find the last time a user authenticated with sudo, along with which pty they used. If a user had used a terminal and successfully authenticated with sudo anytime in the past, and left the sudo file in "/var/lib/sudo//", a malicious user could walk up to an unlocked, logged in machine and gain sudo without knowing the password for the computer. To do this, a user would only need to launch a few terminals, figure out which pty they were on via "tty", find the an instance in /var/log/auth.log where sudo was used on that PTY, and set the clock to that time. Once this is done, they can run (for example) "sudo -s" and have a full access terminal. 1) This has been observed on Ubuntu 13.04, and may work on other versions. 2) This may have an effect on various window managers, but I confirmed it on Unity and Cinnamon 3) I expected to have to authenticate when I changed the time and date, as I do on Gnome and KDE. I also expected to be denied permission to auth.log 4) I was able to change the system time to whatever I wanted, and view auth.log. This was sufficient to access sudo without having to type my password. Note: This bug also affects any version of OS X, though the mechanism is different. Some versions don't require you to authenticate to change the time through the GUI, but some do. No version I've seen requires authentication to use the "systemsetup" command, which can alter the time from the command line. This may be an overall bug in sudo. Why can I bypass security by changing the time?! To manage notifications about this bug go to: https://bugs.launchpad.net/cinnamon-desktop/+bug/1219337/+subscriptions -- Mailing list: https://launchpad.net/~touch-packages Post to : touch-packages@lists.launchpad.net Unsubscribe : https://launchpad.net/~touch-packages More help : https://help.launchpad.net/ListHelp
[Touch-packages] [Bug 1219337] Re: Users can change the clock without authenticating, allowing them to locally exploit sudo.
Just to be clear, you can't currently bypass security by simply changing the time, you also have to guess the tty, and create a new one with the exact timestamp and inode. That information is in a timestamp file you can't access. While adding the monotonic clock is an incremental improvement, it's not a critical issue. -- You received this bug notification because you are a member of Ubuntu Touch seeded packages, which is subscribed to sudo in Ubuntu. https://bugs.launchpad.net/bugs/1219337 Title: Users can change the clock without authenticating, allowing them to locally exploit sudo. Status in Cinnamon: New Status in sudo: Unknown Status in Unity: Invalid Status in policykit-desktop-privileges package in Ubuntu: Opinion Status in sudo package in Ubuntu: Confirmed Bug description: Under unity and cinnamon, it is possible for a user to turn off network-syncronized time and then change the time on the system. It is also possible to "cat /var/log/auth.log" and find the last time a user authenticated with sudo, along with which pty they used. If a user had used a terminal and successfully authenticated with sudo anytime in the past, and left the sudo file in "/var/lib/sudo//", a malicious user could walk up to an unlocked, logged in machine and gain sudo without knowing the password for the computer. To do this, a user would only need to launch a few terminals, figure out which pty they were on via "tty", find the an instance in /var/log/auth.log where sudo was used on that PTY, and set the clock to that time. Once this is done, they can run (for example) "sudo -s" and have a full access terminal. 1) This has been observed on Ubuntu 13.04, and may work on other versions. 2) This may have an effect on various window managers, but I confirmed it on Unity and Cinnamon 3) I expected to have to authenticate when I changed the time and date, as I do on Gnome and KDE. I also expected to be denied permission to auth.log 4) I was able to change the system time to whatever I wanted, and view auth.log. This was sufficient to access sudo without having to type my password. Note: This bug also affects any version of OS X, though the mechanism is different. Some versions don't require you to authenticate to change the time through the GUI, but some do. No version I've seen requires authentication to use the "systemsetup" command, which can alter the time from the command line. This may be an overall bug in sudo. Why can I bypass security by changing the time?! To manage notifications about this bug go to: https://bugs.launchpad.net/cinnamon-desktop/+bug/1219337/+subscriptions -- Mailing list: https://launchpad.net/~touch-packages Post to : touch-packages@lists.launchpad.net Unsubscribe : https://launchpad.net/~touch-packages More help : https://help.launchpad.net/ListHelp
[Touch-packages] [Bug 1219337] Re: Users can change the clock without authenticating, allowing them to locally exploit sudo.
Congratulations, Ubuntu team. You have now fallen behind *Debian's Stable Release* in a security update to sudo, despite several releases in between. They even released their newest (24 month development cycle) in the same month as you. This has been fixed, *fully fixed*, for over a year now. Epic fail. mscs@water:~$ sudo -V Sudo version 1.8.10p3 Sudoers policy plugin version 1.8.10p3 Sudoers file grammar version 43 Sudoers I/O plugin version 1.8.10p3 mscs@water:~$ https://packages.debian.org/search?keywords=sudo https://launchpad.net/ubuntu/+source/sudo -- You received this bug notification because you are a member of Ubuntu Touch seeded packages, which is subscribed to sudo in Ubuntu. https://bugs.launchpad.net/bugs/1219337 Title: Users can change the clock without authenticating, allowing them to locally exploit sudo. Status in Cinnamon: New Status in sudo: Unknown Status in Unity: Invalid Status in policykit-desktop-privileges package in Ubuntu: Opinion Status in sudo package in Ubuntu: Confirmed Bug description: Under unity and cinnamon, it is possible for a user to turn off network-syncronized time and then change the time on the system. It is also possible to "cat /var/log/auth.log" and find the last time a user authenticated with sudo, along with which pty they used. If a user had used a terminal and successfully authenticated with sudo anytime in the past, and left the sudo file in "/var/lib/sudo//", a malicious user could walk up to an unlocked, logged in machine and gain sudo without knowing the password for the computer. To do this, a user would only need to launch a few terminals, figure out which pty they were on via "tty", find the an instance in /var/log/auth.log where sudo was used on that PTY, and set the clock to that time. Once this is done, they can run (for example) "sudo -s" and have a full access terminal. 1) This has been observed on Ubuntu 13.04, and may work on other versions. 2) This may have an effect on various window managers, but I confirmed it on Unity and Cinnamon 3) I expected to have to authenticate when I changed the time and date, as I do on Gnome and KDE. I also expected to be denied permission to auth.log 4) I was able to change the system time to whatever I wanted, and view auth.log. This was sufficient to access sudo without having to type my password. Note: This bug also affects any version of OS X, though the mechanism is different. Some versions don't require you to authenticate to change the time through the GUI, but some do. No version I've seen requires authentication to use the "systemsetup" command, which can alter the time from the command line. This may be an overall bug in sudo. Why can I bypass security by changing the time?! To manage notifications about this bug go to: https://bugs.launchpad.net/cinnamon-desktop/+bug/1219337/+subscriptions -- Mailing list: https://launchpad.net/~touch-packages Post to : touch-packages@lists.launchpad.net Unsubscribe : https://launchpad.net/~touch-packages More help : https://help.launchpad.net/ListHelp