Input validation error in Mozilla products - CVE-2026-124859
Published: November 10, 2026
Vulnerability identifier: #VU164495
CSH Severity: Low
CVSS v4: 8.5 [CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N]
CVE-ID: CVE-2026-124859
CWE-ID: CWE-20
Exploitation vector: Local access
Exploit availability:
No public exploit available
Vulnerability details
The vulnerability allows a local user to escape browser sandbox restrictions.
The vulnerability exists due to incorrect boundary validation in the Storage: Cache API component when handling cache operations across sandbox boundaries. A local user can trigger operations that encounter incorrectly enforced boundaries to escape sandbox restrictions.
Affected software
Firefox for Android
Mozilla Firefox
Firefox ESR
Mozilla Firefox
Firefox ESR
How to mitigate CVE-2026-124859
Install security update from vendor's website.
Firefox for Android - update to 160.0
Mozilla Firefox - update to 160.0
Firefox ESR - addressed in versions 115.45.0, 153.7.0
Mozilla Firefox - update to 160.0
Firefox ESR - addressed in versions 115.45.0, 153.7.0