CVE-2026-124939: Mozilla Firefox · JIT miscompilation in the JavaScript Engine: JIT component
Affects Mozilla FirefoxSource CVE Database V5
Not known to be exploited.
Data as of 10 Nov 2026, 13:37 UTC
Rated High by Threat Radar's AI analysis · CVSS not yet scored by NVD
Thin evidence
One scorer or noneExploitation evidence
Disclosed: evidence found.
CVE published 10 Nov 2026
Detectable: no evidence on record.
No public nuclei template indexed
Weaponized: no evidence on record.
No public exploit code indexed in Metasploit or Exploit-DB
Exploited in the wildExploited: no evidence on record.
Not in CISA KEV and no source reports exploitation
Observed by OffSeq MirageSeen by Mirage: no evidence on record.
No attack traffic recorded by OffSeq Mirage sensors
A missing step is not evidence of safety. Sources: cve.org (opens in a new tab), the Metasploit, Exploit-DB and nuclei-templates index as of 10 Nov 2026.
What to do
AI-suggested
A fix for this vulnerability is available and has been incorporated in Firefox 160 and Firefox ESR 153.7. Users and administrators should update to these versions or later to mitigate the risk. No additional mitigation actions are indicated by the vendor advisory.
Description
CVE-2026-124939 is a vulnerability involving just-in-time (JIT) miscompilation in the JavaScript engine's JIT component of Mozilla Firefox. This flaw was addressed and fixed in Firefox version 160 and Firefox ESR 153.7. The vulnerability is part of a set of high-impact security issues resolved in the same release cycle.