NULL pointer dereference in Mozilla products - CVE-2026-84131
Published: September 1, 2026
Vulnerability identifier: #VU146609
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-2026-84131
CWE-ID: CWE-476
Exploitation vector: Remote access
Exploit availability:
No public exploit available
Vulnerability details
The vulnerability allows a remote attacker to escalate privileges.
The vulnerability exists due to invalid pointer dereference in Graphics component when processing web content. A remote attacker can convince the victim to visit a specially crafted website to escalate privileges.
User interaction is required.
Affected software
Mozilla Firefox
Firefox ESR
Firefox for Android
Firefox ESR
Firefox for Android
How to mitigate CVE-2026-84131
Install security update from vendor's website.
Mozilla Firefox - update to 155.0
Firefox for Android - update to 155.0
Firefox ESR - addressed in versions 115.40.0, 140.15.0, 153.2.0
Firefox for Android - update to 155.0
Firefox ESR - addressed in versions 115.40.0, 140.15.0, 153.2.0
External References
- https://www.mozilla.org/en-US/security/advisories/mfsa2026-83/
- https://www.mozilla.org/en-US/security/advisories/mfsa2026-82/
- https://www.mozilla.org/en-US/security/advisories/mfsa2026-84/
- https://www.mozilla.org/en-US/security/advisories/mfsa2026-85/
- https://bugzilla.mozilla.org/show_bug.cgi?id=2060008