Incorrect calculation in Mozilla products - CVE-2026-124939
Published: November 10, 2026
Vulnerability identifier: #VU164563
CSH Severity: Medium
CVSS v4: 5.1 [CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:A/VC:N/VI:L/VA:L/SC:N/SI:N/SA:N]
CVE-ID: CVE-2026-124939
CWE-ID: CWE-682
Exploitation vector: Remote access
Exploit availability:
No public exploit available
Vulnerability details
The vulnerability allows a remote attacker to trigger incorrect JavaScript execution, potentially disrupting browser operation.
The vulnerability exists due to incorrect just-in-time compilation in the JavaScript Engine: JIT component when compiling JavaScript. A remote attacker can supply JavaScript that is miscompiled to produce incorrect execution results and potentially disrupt browser operation.
Affected software
Firefox ESR
Mozilla Firefox
Firefox for Android
Mozilla Firefox
Firefox for Android
How to mitigate CVE-2026-124939
Install security update from vendor's website.
Firefox ESR - update to 153.7.0
Firefox for Android - update to 160.0
Mozilla Firefox - update to 160.0
Firefox for Android - update to 160.0
Mozilla Firefox - update to 160.0