Use-after-free in Mozilla products - CVE-2026-109719

 

Use-after-free in Mozilla products - CVE-2026-109719

Published: October 16, 2026


Vulnerability identifier: #VU155985
CSH Severity: Medium
CVSS v4: 7.5 [CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:A/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N]
CVE-ID: CVE-2026-109719
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 a race condition leading to use-after-free in the Graphics: CanvasWebGL component when processing WebGL operations. A remote attacker can supply crafted web content that triggers the race and subsequent access to freed memory to crash the browser or potentially execute arbitrary code.


Affected software

Mozilla Firefox
Firefox ESR
Firefox for Android
Debian Linux
firefox-esr (Debian package)

How to mitigate CVE-2026-109719

Install security update from vendor's website.

Mozilla Firefox - update to 158.0
Firefox for Android - update to 158.0
Firefox ESR - addressed in versions 115.43.0, 153.5.0
firefox-esr (Debian package) - update to 153.5.0esr-1~deb13u1

External References

Related Security Bulletins