CVE-2018-18498: Canonical Ubuntu Linux

Critical severity, CVSS 9.8. EPSS: 4% chance of exploitation in the next 30 days.

A potential vulnerability leading to an integer overflow can occur during buffer size calculations for images when a raw value is used instead of the checked value. This leads to a possible out-of-bounds write. This vulnerability affects Thunderbird < 60.4, Firefox ESR < 60.4, and Firefox < 64.

Affected products

• Canonical Ubuntu Linux: version 14.04 only; version 16.04 only; version 18.04 only; version 18.10 only
• Debian Debian Linux: version 8.0 only; version 9.0 only
• Mozilla Firefox: before 64.0 (fixed in 64.0)
• Mozilla Firefox ESR: before 60.4 (fixed in 60.4)
• Mozilla Thunderbird: before 60.4 (fixed in 60.4)
• Red Hat Enterprise Linux Desktop: version 6.0 only; version 7.0 only
• Red Hat Enterprise Linux Server: version 6.0 only; version 7.0 only
• Red Hat Enterprise Linux Server Aus: version 7.6 only
• Red Hat Enterprise Linux Server Eus: version 7.6 only
• Red Hat Enterprise Linux Server Tus: version 7.6 only
• Red Hat Enterprise Linux Workstation: version 6.0 only; version 7.0 only

Published 2019-02-28. Last modified 2026-06-17.