Input validation error in Mozilla Firefox and Firefox for Android - CVE-2026-6777
Published: April 21, 2026
Vulnerability identifier: #VU126691
CSH Severity: Low
CVSS v4.0: CVSS:4.0/AV:N/AC:H/AT:N/PR:N/UI:A/VC:L/VI:N/VA:N/SC:N/SI:N/SA:N/E:U/U:Clear
CVE-ID: CVE-2026-6777
CWE-ID: CWE-20
Exploitation vector: Remote access
Exploit availability:
No public exploit available
Vendor: Mozilla
Affected software:
Mozilla Firefox
Firefox for Android
Mozilla Firefox
Firefox for Android
Detailed vulnerability description
The vulnerability allows a remote attacker to bypass implemented security restrictions.
The vulnerability exists due to an unspecified error in the Networking: DNS component. A remote attacker can bypass implemented security restrictions.
How to mitigate CVE-2026-6777
Install updates from vendor's website.