CVE-2010-0169: Mozilla Firefox

Medium severity, CVSS 5.0. EPSS: 1.7% chance of exploitation in the next 30 days.

The CSSLoaderImpl::DoSheetComplete function in layout/style/nsCSSLoader.cpp in Mozilla Firefox 3.0.x before 3.0.18, 3.5.x before 3.5.8, and 3.6.x before 3.6.2; Thunderbird before 3.0.2; and SeaMonkey before 2.0.3 changes the case of certain strings in a stylesheet before adding this stylesheet to the XUL cache, which might allow remote attackers to modify the browser's font and other CSS attributes, and potentially disrupt rendering of a web page, by forcing the browser to perform this erroneous stylesheet caching.

Affected products

• Mozilla Firefox: version 3.0 only; version 3.0.1 only; version 3.0.10 only; version 3.0.11 only; version 3.0.12 only; version 3.0.13 only; …
• Mozilla Seamonkey: up to and including 2.0.2; version 1.1 only; version 1.1.1 only; version 1.1.2 only; version 1.1.3 only; version 1.1.4 only; …
• Mozilla Thunderbird: up to and including 3.0.1; version 1.5 only; version 1.5.0.1 only; version 1.5.0.2 only; version 1.5.0.3 only; version 1.5.0.4 only; …

Published 2010-03-25. Last modified 2026-06-16.