Use-after-free in Mozilla products - CVE-2026-124862

 

Use-after-free in Mozilla products - CVE-2026-124862

Published: November 10, 2026


Vulnerability identifier: #VU164521
CSH Severity: High
CVSS v4: 8.6 [CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:A/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N]
CVE-ID: CVE-2026-124862
CWE-ID: CWE-416
Exploitation vector: Remote access
Exploit availability: No public exploit available

Vulnerability details

The vulnerability allows a remote attacker to cause a denial of service and potentially execute arbitrary code.

The vulnerability exists due to use-after-free in the DOM: Core & HTML component when processing document content. A remote attacker can supply crafted content that triggers access to freed memory to crash the browser or potentially execute arbitrary code.


Affected software

Firefox ESR
Mozilla Firefox
Firefox for Android

How to mitigate CVE-2026-124862

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

External References