CVE-2026-74936
Use-after-free in the JavaScript: WebAssembly component
CRITICAL 9.8EPSS 0.6%
Use-after-free in the JavaScript: WebAssembly component. This vulnerability was fixed in Firefox 154, Firefox ESR 140.14, Firefox ESR 153.1, Thunderbird 154, Thunderbird 140.14, and Thunderbird 153.1.
- 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 - EPSS
- 0.59% chance of exploitation in the next 30 days, 47th percentile
- Published
- 2026-08-18
- Updated
- 2026-08-21
Proof-of-concept exploits (1)
- SneakyNachos/CVE-2026-74936-gc-potato0★ · 2026-08-27
Security advisories
- https://www.mozilla.org/security/advisories/mfsa2026-74
- https://www.mozilla.org/security/advisories/mfsa2026-76
- https://www.mozilla.org/security/advisories/mfsa2026-77
- https://www.mozilla.org/security/advisories/mfsa2026-78
- https://www.mozilla.org/security/advisories/mfsa2026-79
- https://www.mozilla.org/security/advisories/mfsa2026-80