CVE-2008-4066: Mozilla Firefox

Medium severity, CVSS 4.3. EPSS: 1.8% chance of exploitation in the next 30 days.

Mozilla Firefox 2.0.0.14, and other versions before 2.0.0.17, allows remote attackers to bypass cross-site scripting (XSS) protection mechanisms and conduct XSS attacks via HTML-escaped low surrogate characters that are ignored by the HTML parser, as demonstrated by a "jav&#56325ascript" sequence, aka "HTML escaped low surrogates bug."

Affected products

• Mozilla Firefox: version 2.0.0.14 only; version 2.0.0.15 only; version 2.0.0.16 only

Published 2008-09-24. Last modified 2026-06-16.