CVE-2019-11758: Canonical Ubuntu Linux

High severity, CVSS 8.8. EPSS: 1.3% chance of exploitation in the next 30 days.

Mozilla community member Philipp reported a memory safety bug present in Firefox 68 when 360 Total Security was installed. This bug showed evidence of memory corruption in the accessibility engine and we presume that with enough effort that it could be exploited to run arbitrary code. This vulnerability affects Firefox < 69, Thunderbird < 68.2, and Firefox ESR < 68.2.

Affected products

• Canonical Ubuntu Linux: version 16.04 only
• Mozilla Firefox: before 69.0 (fixed in 69.0)
• Mozilla Firefox ESR: before 68.2 (fixed in 68.2)
• Mozilla Thunderbird: before 68.2 (fixed in 68.2)

Published 2020-01-08. Last modified 2026-06-17.