Use-after-free in Mozilla products - CVE-2026-117933
Published: October 27, 2026
Vulnerability identifier: #VU158162
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-2026-117933
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 unsafe access to poisoned layout-frame memory in the CSS Parsing and Computation component when processing styles. A remote attacker can supply crafted content to trigger invalid frame access and potentially crash the browser.
Affected software
Firefox ESR
Mozilla Firefox
Firefox for Android
Mozilla Firefox
Firefox for Android
How to mitigate CVE-2026-117933
Install security update from vendor's website.
Firefox ESR - update to 153.6.0
Firefox for Android - update to 159.0
Mozilla Firefox - update to 159.0
Firefox for Android - update to 159.0
Mozilla Firefox - update to 159.0