CVE-2010-0654: Mozilla Firefox

Medium severity, CVSS 4.3. EPSS: 1.9% chance of exploitation in the next 30 days.

Mozilla Firefox 3.5.x before 3.5.11 and 3.6.x before 3.6.7, Thunderbird 3.0.x before 3.0.6 and 3.1.x before 3.1.1, and SeaMonkey before 2.0.6 permit cross-origin loading of CSS stylesheets even when the stylesheet download has an incorrect MIME type and the stylesheet document is malformed, which allows remote attackers to obtain sensitive information via a crafted document.

Affected products

• Mozilla Firefox: version 3.5.1 only; version 3.5.2 only; version 3.5.3 only; version 3.5.4 only; version 3.5.5 only; version 3.5.6 only; …
• Mozilla Seamonkey: up to and including 2.0.5; version 1.0 only; version 1.0.1 only; version 1.0.2 only; version 1.0.3 only; version 1.0.4 only; …
• Mozilla Thunderbird: version 3.0.1 only; version 3.0.2 only; version 3.0.3 only; version 3.0.4 only; version 3.0.5 only; version 3.1 only

Published 2010-02-18. Last modified 2026-06-16.