Hi,
   Just wanted to share some info   
Exploit 1.
Register an account for MSN messenger, make some
contact email addresses, leave the account for 31
days. On a different machine (to ensure there's
no cache), go to the sign up section of MSN
messenger, sign up again, using the same screen
name. You'll be able to see the previous user's
contact list.

None of the contacts will have been alerted to
the fact that the new username actully belong to
an entirely different person, so they'll still be
sending messages, and if the new user is a haxor,
(s)he'll be replying just as if (s)he's the
original user.

I alerted Microsoft on monday, and have recieved
no reply. so there. :)


Exploit 2
MSN Messenger (and Windows Messenger on XP) 
can be used to obtain personal information about a 
user from any website (in any domain).

Using JavaScript a user's display name can be 
obtained from Messenger, as well as the display 
names of all their contacts. For users who have a 
sensible and accurate display name this should be 
considered a privacy issue. (Note: anyone who has 
not set a display name at all, will reveal their email 
address instead.)

Using the same technique web sites hosted on 
certain domains (microsoft.com, hotmail.com & 
hotmail.msn.com) can also access the email 
address of the user (along with the email addresses 
of all their contacts). This could be used by Microsoft 
to track users on their sites, which many would 
consider to be a privacy issue.

In addition to the three domains mentioned above, 
additional domains can be allowed access to the 
email addresses with a single registry entry. This 
registry entry could be made by spyware/adware 
installed by a user (sometimes unknowingly along 
with a piece of shareware). Once there you have the 
potential to give your email address to any site that 
requests it and places it in a cookie.



Technical
=========

Microsoft designed Messenger to allow functionality 
to be used in webpages using JavaScript or 
VBScript. This includes the ability to view the display 
name and email address of the user and their 
contacts. In an attempt to protect users only a certain 
selection of sites can use script to get email 
addresses, but all can get display names.

The list of domain suffixes that have full access to 
Messenger functionality (email addresses & more?) 
can be found in the registry in 
key "HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft
\MessengerService\Policies\Suffixes". 
Values "Suffix0", "Suffix1", etc. By default there are
no 
entries in the list, but they can be added. E.g. adding 
value Suffix0 = "test.com" will give web sites in the 
test.com domain full access to Messenger 
information.

Full domains do not have to be specified in the list, 
adding "com" would allow all .com sites to have full 
access.

Although by default there are no entries in this list, 
three domains (listed above) are hard coded into 
Messenger for the same purpose. These allow 
Microsoft to make their sites (e.g. Hotmail) look nice 
by integrating messenger features into them. The 
user cannot remove the special status applied to 
these sites.

The only way for a user to prevent sites having any 
access to their information is by logging out of 
Messenger before visiting.

Recommendations

- Set a display name so your email address isn't 
obtainable so easily.
- Check for entries 
in "HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
MessengerService\Policies\Suffixes" regularly, 
especially after installing freeware or shareware.
- If you want to visit microsoft.com and remain 
anonymous, close MSN Messenger.


--
This mail is from the lpi-india mailing list.

Reply via email to