Use-after-free in Mozilla products - CVE-2026-124857

 

Use-after-free in Mozilla products - CVE-2026-124857

Published: November 10, 2026


Vulnerability identifier: #VU164493
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-2026-124857
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 Graphics: Canvas2D component when processing two-dimensional canvas operations. A remote attacker can supply crafted web content that triggers access to freed memory during canvas processing to crash the browser process or potentially execute arbitrary code.


Affected software

Firefox for Android
Mozilla Firefox
Firefox ESR

How to mitigate CVE-2026-124857

Install security update from vendor's website.

Firefox for Android - update to 160.0
Mozilla Firefox - update to 160.0
Firefox ESR - addressed in versions 115.45.0, 153.7.0

External References