Use-after-free in Mozilla products - CVE-2026-117870

 

Use-after-free in Mozilla products - CVE-2026-117870

Published: October 27, 2026


Vulnerability identifier: #VU158070
CSH Severity: Medium
CVSS v4: 6.9 [CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:A/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N]
CVE-ID: CVE-2026-117870
CWE-ID: CWE-416
Exploitation vector: Remote access
Exploit availability: No public exploit available

Vulnerability details

The vulnerability allows a remote attacker to potentially cause a denial of service.

The vulnerability exists due to use-after-free in the JavaScript engine when processing scripts. A remote attacker can supply crafted script content to trigger access to freed memory and potentially crash the browser.


Affected software

Mozilla Firefox
Firefox ESR
Firefox for Android

How to mitigate CVE-2026-117870

Install security update from vendor's website.

Mozilla Firefox - update to 159.0
Firefox for Android - update to 159.0
Firefox ESR - addressed in versions 115.44.0, 153.6.0

External References

Related Security Bulletins