CVE-2026-74939
Privilege escalation in the DOM: Navigation component
HIGH 8.8EPSS 0.5%
Privilege escalation in the DOM: Navigation component. This vulnerability was fixed in Firefox 154, Firefox ESR 115.39, Firefox ESR 140.14, Firefox ESR 153.1, Thunderbird 154, Thunderbird 140.14, and Thunderbird 153.1.
- Affected
- Mozilla · Firefox · Thunderbird
- CVSS v3.1 CNA
- 8.8 HIGH
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H - EPSS
- 0.45% chance of exploitation in the next 30 days, 38th percentile
- Published
- 2026-08-18
- Updated
- 2026-08-21
Proof-of-concept exploits (1)
- SneakyNachos/CVE-2026-74939-escape-the-mac-n-cheese-box1★ · 2026-08-24
Security advisories
- https://www.mozilla.org/security/advisories/mfsa2026-74
- https://www.mozilla.org/security/advisories/mfsa2026-75
- 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