A new vulnerability has been reported in phpBB, allowing malicious people to conduct Cross Site Scripting attacks.

An Input passed to various parameters in certain scripts isn’t properly sanitised by phpBB scripts before being returned to the user. This can be exploited to execute arbitrary HTML and script code in a user’s browser session in context of a vulnerable site.

Vulnerable scripts:
search.php using the “search_author” parameter.
privmsg.php using the “mode” parameter.
login.php using the “redirect” parameter.

Note: “privmsg.php” and “login.php” are vulnerable to a Cross Site Scripting variant often referred to as “CRLF” header injection or “HTTP Response Splitting”.

This vulnerability affects version 2.0.9 and prior.

Solution: Reportedly this has been fixed in version 2.0.10.