Use-after-free in Mozilla products - CVE-2026-6759
Published: April 21, 2026
Vulnerability identifier: #VU126667
CSH Severity: Low
CVSS v4.0: CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:U/U:Clear
CVE-ID: CVE-2026-6759
CWE-ID: CWE-416
Exploitation vector: Local access
Exploit availability:
No public exploit available
Vendor: Mozilla
Affected software:
Mozilla Firefox
Firefox ESR
Firefox for Android
Mozilla Firefox
Firefox ESR
Firefox for Android
Detailed vulnerability description
The vulnerability allows a local user to cause a denial of service.
The vulnerability exists due to use-after-free in the Widget: Cocoa component when handling local widget operations. A local user can trigger the vulnerable code path to cause a denial of service.
How to mitigate CVE-2026-6759
Install security update from vendor's website.