CVE-2012-1964: Mozilla Firefox

Medium severity, CVSS 4.0. EPSS: 0.9% chance of exploitation in the next 30 days.

The certificate-warning functionality in browser/components/certerror/content/aboutCertError.xhtml in Mozilla Firefox 4.x through 12.0, Firefox ESR 10.x before 10.0.6, Thunderbird 5.0 through 12.0, Thunderbird ESR 10.x before 10.0.6, and SeaMonkey before 2.10 does not properly handle attempted clickjacking of the about:certerror page, which allows man-in-the-middle attackers to trick users into adding an unintended exception via an IFRAME element.

Affected products

• Mozilla Firefox: version 4.0 only; version 4.0.1 only; version 5.0 only; version 5.0.1 only; version 6.0 only; version 6.0.1 only; …
• Mozilla Seamonkey: up to and including 2.0.14; 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 5.0 only; version 6.0 only; version 6.0.1 only; version 6.0.2 only; version 7.0 only; version 7.0.1 only; …
• Mozilla Thunderbird ESR: version 10.0 only; version 10.0.1 only; version 10.0.2 only; version 10.0.3 only; version 10.0.4 only; version 10.0.5 only

Published 2012-07-18. Last modified 2026-06-16.