Secunia

A vulnerability has been reported in ExpressionEngine, which can be exploited by malicious users to conduct script insertion attacks.

Input passed via the "avatar" parameter in system/index.php (when "M" is set to "select_avatar" and "C" is set to "myaccount") is not properly sanitised before being used. This can be exploited to insert arbitrary HTML and script code, which will be executed in a user's browser session in the context of an affected site when the malicious avatar is displayed.

The vulnerability is reported in versions 1.6.4 to 1.6.6.

Solution
The vulnerability is reportedly fixed in version 1.6.7.

Provided and/or discovered by
Adam Baldwin, nGenuity Information Services

Changelog
Further details available in Customer Area

Original Advisory
nGenuity:
http://www.ngenuity.org/wordpress/2009/01/28/ngenuity-2009-003-expressionengine-persistent-cross-site-scripting/

ExpressionEngine:
http://expressionengine.com/docs/changelog.html#v167

Deep Links
Links available in Customer Area