CVE-2016-2821: Canonical Ubuntu Linux

High severity, CVSS 7.5. EPSS: 2.8% chance of exploitation in the next 30 days.

Use-after-free vulnerability in the mozilla::dom::Element class in Mozilla Firefox before 47.0 and Firefox ESR 45.x before 45.2, when contenteditable mode is enabled, allows remote attackers to execute arbitrary code or cause a denial of service (heap memory corruption) by triggering deletion of DOM elements that were created in the editor.

Affected products

• Canonical Ubuntu Linux: version 12.04 only; version 14.04 only; version 15.10 only; version 16.04 only
• Debian Debian Linux: version 8.0 only
• Mozilla Firefox: up to and including 46.0.1; version 45.1.0 only; version 45.1.1 only
• Opensuse Leap: version 42.1 only
• Opensuse Opensuse: version 13.1 only; version 13.2 only

Published 2016-06-13. Last modified 2026-06-17.