CVE-2026-4711
9.8
CRITICAL
CVSS 3.1
EPSS 0.03%
Description
Use-after-free in the Widget: Cocoa component. This vulnerability affects Firefox < 149, Firefox ESR < 140.9, Thunderbird < 149, and Thunderbird < 140.9.
How to fix CVE-2026-4711
No fixed version has been published yet. Mitigate by removing the affected package or applying upstream guidance from the references below.
- Debian/firefox-esr—no fix listed
- Debian/thunderbird—no fix listed
Is CVE-2026-4711 being exploited?
Low — EPSS is 0.0%, meaning exploitation activity has not been observed at scale.
Affected packages (2)
- from 0
- from 0
CVSS scores
| Source | Version | Severity | Vector |
|---|---|---|---|
| osv | CVSS 3.1 | CRITICAL9.8 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H |