Product: vBulletin
Version: 3 - 4.1.3
Release Date: 06/02/2011
Risk: Low
Authentication: Not required to exploit.
Remote: Yes

Description: 
Multiple Open Redirect vulnerabilities in vBulletin version 4.1.3 and below allow remote attackers to redirect users to arbitrary web sites and conduct phishing attacks via the "url" parameter. By appending ?url=http://attackersite.com any number of pages, the user will be redirected to a potentially dangerous site. This is particularly interesting when used on the registration form or the password reset form. 

Exploit Example:
http://forum.pwndshop.com/register.php?do=checkdate&url=http://attackersite.com

Vendor Notified: Yes

Reference: 
http://www.vbulletin.com/forum/showthread.php/381014-Potential-Phishing-Vector?p=2166441
https://www.owasp.org/index.php/Open_redirect

Credit:

Robert Gilbert
Senior Consultant
HALOCK Security Labs, Purpose Driven Security(tm)
rgilbert [-at-] halock [-dot-] com 
http://www.halock.com 
http://blog.halock.com 


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