CVE-2026-4689 - Vulnerability Analysis
CriticalCVSS: 10.0Last Updated: March 25, 2026
Firefox - Sandbox Escape
Published: March 24, 2026Updated: March 25, 2026Remote Exploitable
Overview
Firefox < 149, Firefox ESR < 115.34, and Firefox ESR < 140.9 contain a sandbox escape caused by integer overflow in the XPCOM component, letting attackers escape sandbox restrictions, exploit requires crafted input.
Severity & Score
Severity: Critical
CVSS Score: 10.0
Impact
Attackers can escape sandbox restrictions, potentially leading to full system compromise.
Mitigation
Update to Firefox 149, Firefox ESR 115.34, Firefox ESR 140.9 or later.
References
- https://bugzilla.mozilla.org/show_bug.cgi?id=2016374
- https://www.mozilla.org/security/advisories/mfsa2026-20/
- https://www.mozilla.org/security/advisories/mfsa2026-21/
- https://www.mozilla.org/security/advisories/mfsa2026-22/
- https://www.mozilla.org/security/advisories/mfsa2026-23/
- https://www.mozilla.org/security/advisories/mfsa2026-24/
Related Resources
Details
- CVE ID
- CVE-2026-4689
- Severity
- Critical
- CVSS Score
- 10.0
- Type
- integer_overflow
- Status
- confirmed
CWE
- CWE-190
- CWE-120
CVSS Metrics
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H