Use-after-free in Mozilla Firefox and Firefox for Android - CVE-2026-6758
Published: April 21, 2026
Vulnerability identifier: #VU126680
CSH Severity: Medium
CVSSv4.0: 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/E:U/U:Green
CVE-ID: CVE-2026-6758
CWE-ID: CWE-416
Exploitation vector: Remote access
Exploit availability:
No public exploit available
Vulnerable software:
Mozilla Firefox
Firefox for Android
Mozilla Firefox
Firefox for Android
Software vendor:
Mozilla
Mozilla
Description
The vulnerability allows a remote attacker to cause a denial of service.
The vulnerability exists due to use-after-free in the JavaScript: WebAssembly component when processing WebAssembly content. A remote attacker can trigger use of a dangling object to cause a denial of service.
Remediation
Install security update from vendor's website.