CVE-2008-5012: Mozilla Firefox

Medium severity, CVSS 5.0. EPSS: 2% chance of exploitation in the next 30 days.

Mozilla Firefox 2.x before 2.0.0.18, Thunderbird 2.x before 2.0.0.18, and SeaMonkey 1.x before 1.1.13 do not properly change the source URI when processing a canvas element and an HTTP redirect, which allows remote attackers to bypass the same origin policy and access arbitrary images that are not directly accessible to the attacker. NOTE: this issue can be leveraged to enumerate software on the client by performing redirections related to moz-icon.

Affected products

• Mozilla Firefox: up to and including 2.0.0.17; version 0.8 only; version 0.9 only; version 0.9.1 only; version 0.9.2 only; version 0.9.3 only; …
• Mozilla Seamonkey: up to and including 1.1.12; 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 2.0.0.17; version 0.1 only; version 0.2 only; version 0.3 only; version 0.4 only; version 0.5 only; …

Published 2008-11-13. Last modified 2026-06-16.