CVE-2012-4182: Canonical Ubuntu Linux

High severity, CVSS 9.3. EPSS: 4.7% chance of exploitation in the next 30 days.

Use-after-free vulnerability in the nsTextEditRules::WillInsert function in Mozilla Firefox before 16.0, Firefox ESR 10.x before 10.0.8, Thunderbird before 16.0, Thunderbird ESR 10.x before 10.0.8, and SeaMonkey before 2.13 allows remote attackers to execute arbitrary code or cause a denial of service (heap memory corruption) via unspecified vectors.

Affected products

• Canonical Ubuntu Linux: version 10.04 only; version 11.04 only; version 11.10 only; version 12.04 only
• Debian Debian Linux: version 6.0 only
• Mozilla Firefox: before 10.0.8 (fixed in 10.0.8); before 16.0 (fixed in 16.0)
• Mozilla Seamonkey: before 2.13 (fixed in 2.13)
• Mozilla Thunderbird: before 16.0 (fixed in 16.0)
• Mozilla Thunderbird ESR: before 10.0.8 (fixed in 10.0.8)
• Red Hat Enterprise Linux Desktop: version 5.0 only; version 6.0 only
• Red Hat Enterprise Linux Eus: version 6.3 only
• Red Hat Enterprise Linux Server: version 5.0 only; version 6.0 only
• Red Hat Enterprise Linux Workstation: version 5.0 only; version 6.0 only
• Suse Linux Enterprise Desktop: version 10 only; version 11 only
• Suse Linux Enterprise SDK: version 10 only
• Suse Linux Enterprise Server: version 10 only; version 11 only

Published 2012-10-10. Last modified 2026-06-16.