CVE-2011-2999: Mozilla Firefox

Medium severity, CVSS 4.3. EPSS: 1.1% chance of exploitation in the next 30 days.

Mozilla Firefox before 3.6.23 and 4.x through 5, Thunderbird before 6.0, and SeaMonkey before 2.3 do not properly handle "location" as the name of a frame, which allows remote attackers to bypass the Same Origin Policy via a crafted web site, a different vulnerability than CVE-2010-0170.

Affected products

• Mozilla Firefox: up to and including 3.6.22; version 3.6 only; version 3.6.2 only; version 3.6.3 only; version 3.6.4 only; version 3.6.6 only; …
• Mozilla Seamonkey: up to and including 2.1; 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: up to and including 5.0; version 0.1 only; version 0.2 only; version 0.3 only; version 0.4 only; version 0.5 only; …

Published 2011-09-29. Last modified 2026-06-16.