CVE-2013-0756: Canonical Ubuntu Linux

High severity, CVSS 9.3. EPSS: 4.2% chance of exploitation in the next 30 days.

Use-after-free vulnerability in the obj_toSource function in Mozilla Firefox before 18.0, Firefox ESR 17.x before 17.0.2, Thunderbird before 17.0.2, Thunderbird ESR 17.x before 17.0.2, and SeaMonkey before 2.15 allows remote attackers to execute arbitrary code via a crafted web page referencing JavaScript Proxy objects that are not properly handled during garbage collection.

Affected products

• Canonical Ubuntu Linux: version 10.04 only; version 11.10 only; version 12.04 only; version 12.10 only
• Mozilla Firefox: before 17.0.2 (fixed in 17.0.2); before 18.0 (fixed in 18.0)
• Mozilla Seamonkey: before 2.15 (fixed in 2.15)
• Mozilla Thunderbird: before 17.0.2 (fixed in 17.0.2)
• Mozilla Thunderbird ESR: before 17.0.2 (fixed in 17.0.2)
• Opensuse Opensuse: version 11.4 only; version 12.1 only; version 12.2 only
• Suse Linux Enterprise Desktop: version 10 only; version 11 only
• Suse Linux Enterprise Server: version 10 only; version 11 only
• Suse Linux Enterprise Software Development Kit: version 10 only; version 11 only

Published 2013-01-13. Last modified 2026-06-16.