[SA18688] PHPX "url" XCode Script Insertion Vulnerability

TITLE:
PHPX "url" XCode Script Insertion Vulnerability

SECUNIA ADVISORY ID:
SA18688

VERIFY ADVISORY:
http://secunia.com/advisories/18688/

CRITICAL:
Moderately critical

IMPACT:
Cross Site Scripting

WHERE:
>From remote

SOFTWARE:
PHPX 3.x
http://secunia.com/product/2967/

DESCRIPTION:
Thomas Pollet has discovered a vulnerability in PHPX, which can be
exploited by malicious people to conduct script insertion attacks.

Input passed via the "url" XCode tag when posting a message isn't
properly verified, before being used. This can be exploited to inject
arbitrary script code, which will be executed in a user's browser
session in context of an affected site when a malicious link with the
"JavaScript" URI handler is followed from a malicious message.

Example:
[url=javascript:[code]]text[/url]

The vulnerability has been confirmed in version 3.5.9. Other versions
may also be affected.

SOLUTION:
Edit the source code to ensure that input is properly sanitised.

PROVIDED AND/OR DISCOVERED BY:
Thomas Pollet

About:
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