CVE-2008-5052: Mozilla Firefox

High severity, CVSS 10.0. EPSS: 3.4% chance of exploitation in the next 30 days.

The AppendAttributeValue function in the JavaScript engine in 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 allows remote attackers to cause a denial of service (crash) via unknown vectors that trigger memory corruption, as demonstrated by e4x/extensions/regress-410192.js.

Affected products

• Mozilla Firefox: from 2.0, before 2.0.0.18 (fixed in 2.0.0.18)
• Mozilla Seamonkey: from 1.0, up to and including 1.1.13
• Mozilla Thunderbird: from 2.0, before 2.0.0.18 (fixed in 2.0.0.18)

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