A vulnerability has been discovered in Firefox, which can be exploited by malicious people to compromise a user's system.

The problem is that Firefox registers the "firefoxurl://" URI handler and allows invoking firefox with arbitrary command line arguments. Using e.g. the "-chrome" parameter it is possible to execute arbitrary Javascript in chrome context. This can be exploited to execute arbitrary commands e.g. when a user visits a malicious web site using Microsoft Internet Explorer.

The vulnerability is confirmed in Firefox version 2.0.0.4 on a fully patched Windows XP SP2. Other versions may also be affected.

Solution
Update to version 2.0.0.5.

Provided and/or discovered by
Billy (BK) Rios, Nate Mcfeters, and Raghav "the Pope" Dube

Additional information provided by Thor Larholm.

Independently discovered by Greg MacManus, iDefense Labs.

Changelog
Further details available to Secunia VIM customers

Original Advisory
Mozilla:
http://www.mozilla.org/security/announce/2007/mfsa2007-23.html

http://www.xs-sniper.com/sniperscope/IE-Pwns-Firefox.html

http://larholm.com/2007/07/10/internet-explorer-0day-exploit/

iDefense:
http://labs.idefense.com/intelligence/vulnerabilities/display.php?id=565

Other references
Further details available to Secunia VIM customers

Alternate/detailed remediation
Further details available in Customer Area

Deep Links
Links available to Secunia VIM customers