CVE-2009-0356: Mozilla Firefox

Medium severity, CVSS 5.1. EPSS: 3.2% chance of exploitation in the next 30 days.

Mozilla Firefox before 3.0.6 and SeaMonkey do not block links to the (1) about:plugins and (2) about:config URIs from .desktop files, which allows user-assisted remote attackers to bypass the Same Origin Policy and execute arbitrary code with chrome privileges via vectors involving the URL field in a Desktop Entry section of a .desktop file, related to representation of about: URIs as jar:file:// URIs. NOTE: this issue exists because of an incomplete fix for CVE-2008-4582.

Affected products

• Mozilla Firefox: up to and including 3.0.5; version 0.1 only; version 0.2 only; version 0.3 only; version 0.4 only; version 0.5 only; …

Published 2009-02-04. Last modified 2026-06-16.