CVE-2026-2766
Use-after-free in the JavaScript Engine: JIT component
CRITICAL 9.8EPSS 0.6%
Use-after-free in the JavaScript Engine: JIT component. This vulnerability was fixed in Firefox 148, Firefox ESR 140.8, Thunderbird 148, and Thunderbird 140.8.
- Affected
- Mozilla · Firefox · Thunderbird
- CVSS v3.1 NVD
- 9.8 CRITICAL
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H - CVSS v3.1 CNA
- 7.5 HIGH
CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:H/I:H/A:H - EPSS
- 0.61% chance of exploitation in the next 30 days, 48th percentile
- Published
- 2026-02-24
- Updated
- 2026-07-15
Proof-of-concept exploits (1)
- SneakyNachos/CVE-2026-2766-but-with-wasm1★ · 2026-08-12
Security advisories
- https://www.mozilla.org/security/advisories/mfsa2026-13
- https://www.mozilla.org/security/advisories/mfsa2026-15
- https://www.mozilla.org/security/advisories/mfsa2026-16
- https://www.mozilla.org/security/advisories/mfsa2026-17
- https://bugzilla.mozilla.org/show_bug.cgi?id=2013583