CVE-2006-1730: Mozilla Firefox

High severity, CVSS 9.3. EPSS: 10.3% chance of exploitation in the next 30 days.

Integer overflow in Mozilla Firefox and Thunderbird 1.x before 1.5.0.2 and 1.0.x before 1.0.8, Mozilla Suite before 1.7.13, and SeaMonkey before 1.0.1 allows remote attackers to execute arbitrary code via a large number in the CSS letter-spacing property that leads to a heap-based buffer overflow.

Affected products

• Mozilla Firefox: version 1.0 only; version 1.0.1 only; version 1.0.2 only; version 1.0.3 only; version 1.0.4 only; version 1.0.5 only; …
• Mozilla Mozilla Suite: version 1.7.6 only; version 1.7.7 only; version 1.7.8 only; version 1.7.10 only; version 1.7.11 only; version 1.7.12 only
• Mozilla Seamonkey: version 1.0 only
• Mozilla Thunderbird: version 1.0 only; version 1.0.1 only; version 1.0.2 only; version 1.0.3 only; version 1.0.4 only; version 1.0.5 only; …

Published 2006-04-14. Last modified 2026-06-16.