Protection Mechanism Failure in Mozilla products - CVE-2026-6771
Published: April 21, 2026
Vulnerability identifier: #VU126675
CSH Severity: Medium
CVSS v4.0: CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:A/VC:L/VI:L/VA:N/SC:N/SI:N/SA:N/E:U/U:Green
CVE-ID: CVE-2026-6771
CWE-ID: CWE-693
Exploitation vector: Remote 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 remote attacker to bypass a security restriction.
The vulnerability exists due to improper restriction enforcement in the DOM: Security component when processing crafted web content. A remote attacker can trigger the vulnerable behavior to bypass a security restriction.
User interaction is required to visit a specially crafted website or URL.
How to mitigate CVE-2026-6771
Install security update from vendor's website.