CVE-2026-124870: Mozilla Firefox · Incorrect boundary conditions in the JavaScript: GC component
Affects Mozilla FirefoxSource CVE Database V5
Not known to be exploited · CVSS 8.8 High.
Data as of 10 Nov 2026, 15:04 UTC
Thin evidence
One scorer or none| CISA-ADP | CVSS 3.1 | 8.8 |
|---|
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:HExploitation 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
Users and administrators should update Firefox to version 160 or later, or Firefox ESR 153.7 or later, where this vulnerability has been fixed. Applying these official updates fully mitigates the risk from this vulnerability.
Description
Incorrect boundary conditions in the JavaScript: GC component. This vulnerability was fixed in Firefox 160 and Firefox ESR 153.7.