Use-after-free in Firefox for Android and Mozilla Firefox - CVE-2026-2799
Published: February 25, 2026
Vulnerability identifier: #VU123236
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-2026-2799
CWE-ID: CWE-416
Exploitation vector: Remote access
Exploit availability:
No public exploit available
Vulnerability details
The vulnerability allows a remote attacker to compromise vulnerable system.
The vulnerability exists due to a use-after-free error in the DOM: Core & HTML component. A remote attacker can trick the victim into visiting a specially crafted website and execute arbitrary code on the system.
Affected software
Firefox for Android
Mozilla Firefox
Mozilla Thunderbird
Mozilla Firefox
Mozilla Thunderbird
How to mitigate CVE-2026-2799
Install updates from vendor's website.
Firefox for Android - update to 148.0
Mozilla Firefox - update to 148.0
Mozilla Thunderbird - update to 148.0
Mozilla Firefox - update to 148.0
Mozilla Thunderbird - update to 148.0