CVE-2005-2270: Mozilla Firefox

High severity, CVSS 7.5. EPSS: 6% chance of exploitation in the next 30 days.

Firefox before 1.0.5 and Mozilla before 1.7.9 does not properly clone base objects, which allows remote attackers to execute arbitrary code by navigating the prototype chain to reach a privileged object.

Affected products

• Mozilla Firefox: version 0.8 only; version 0.9 only; version 0.9.1 only; version 0.9.2 only; version 0.9.3 only; version 0.10 only; …
• Mozilla Mozilla: version 1.3 only; version 1.4 only; version 1.4.1 only; version 1.5 only; version 1.5.1 only; version 1.6 only; …

Published 2005-07-13. Last modified 2026-06-16.