CVE-2019-11740: Canonical Ubuntu Linux

High severity, CVSS 8.8. EPSS: 1.6% chance of exploitation in the next 30 days.

Mozilla developers and community members reported memory safety bugs present in Firefox 68, Firefox ESR 68, and Firefox 60.8. Some of these bugs showed evidence of memory corruption and we presume that with enough effort that some of these could be exploited to run arbitrary code. This vulnerability affects Firefox < 69, Thunderbird < 68.1, Thunderbird < 60.9, Firefox ESR < 60.9, and Firefox ESR < 68.1.

Affected products

• Canonical Ubuntu Linux: version 16.04 only; version 18.04 only; version 19.04 only
• Mozilla Firefox: before 60.9.0 (fixed in 60.9.0); before 69.0 (fixed in 69.0)
• Mozilla Firefox ESR: from 68.0, before 68.1.0 (fixed in 68.1.0)
• Mozilla Thunderbird: before 60.9.0 (fixed in 60.9.0); from 68.0, before 68.1.0 (fixed in 68.1.0)
• Opensuse Leap: version 15.0 only; version 15.1 only

Published 2019-09-27. Last modified 2026-06-17.