CVE-2026-8974
8.8
HIGH
CVSS 3.1
EPSS 0.04%
Description
Memory safety bugs present in Firefox ESR 140.10 and Firefox 150. Some of these bugs showed evidence of memory corruption and we presume that with enough effort some of these could have been exploited to run arbitrary code. This vulnerability was fixed in Firefox 151, Firefox ESR 140.11, Thunderbird 151, and Thunderbird 140.11.
How to fix CVE-2026-8974
To remediate CVE-2026-8974, upgrade the affected package to a fixed version below.
- —upgrade to 140.11.0esr-1~deb11u1 or later
- —upgrade to 1:140.11.0esr-1~deb11u1 or later
Is CVE-2026-8974 being exploited?
Low — EPSS is 0.0%, meaning exploitation activity has not been observed at scale.
Affected packages (2)
- from 0, < 140.11.0esr-1~deb11u1
- from 0, < 1:140.11.0esr-1~deb11u1
CVSS scores
| Source | Version | Severity | Vector |
|---|---|---|---|
| osv | CVSS 3.1 | HIGH8.8 | CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H |