CVE-2026-124917: Sandbox Escape Due to Use-after-free
Source GCVE Database
Not known to be exploited · CVSS 9.6 Critical.
Data as of 10 Nov 2026, 16:47 UTC
Thin evidence
One scorer or none| CISA-ADP | CVSS 3.1 | 9.6 |
|---|
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/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 is fixed. Applying these official patches fully mitigates the risk. No additional mitigation steps are required beyond updating to the fixed versions.
Description
A critical use-after-free vulnerability in the Widget: Gtk component of Firefox allows sandbox escape. This flaw was addressed and fixed in Firefox 160 and Firefox ESR 153.7. The vulnerability has a high CVSS score of 9.6, indicating severe impact on confidentiality, integrity, and availability.