Details
- Type
- Sandbox Escape
- Impact
- Privilege Escalation
- CVSS vector
- CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:H/I:H/A:H
- Published
- 29 September 2026
- Updated
- 15 October 2026
- Weakness
- CWE-416
Vendor fix
Update to Firefox ESR 153.4, Firefox 157, Firefox ESR 115.42, Firefox ESR 140.17 or later.
Patching closes this CVE. It does not tell you which of your systems run the affected version, or what else is exposed alongside them.
References
- https://nvd.nist.gov/vuln/detail/CVE-2026-100778
- https://www.mozilla.org/security/advisories/mfsa2026-100/
- https://www.mozilla.org/security/advisories/mfsa2026-97/
- https://www.mozilla.org/security/advisories/mfsa2026-98/
- https://www.mozilla.org/security/advisories/mfsa2026-99/
- https://www.mozilla.org/security/advisories/mfsa2026-101/
- https://www.mozilla.org/security/advisories/mfsa2026-102/
- https://www.mozilla.org/security/advisories/mfsa2026-103/
- https://bugzilla.mozilla.org/show_bug.cgi?id=2068406