Out-of-bounds read in Mozilla Firefox and Firefox for Android - CVE-2026-12303
Published: June 16, 2026
Vulnerability identifier: #VU134637
CSH Severity: Medium
CVSS v4.0: CVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:A/VC:H/VI:N/VA:N/SC:N/SI:N/SA:N/E:U/U:Green
CVE-ID: CVE-2026-12303
CWE-ID: CWE-125
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 disclose sensitive information.
The vulnerability exists due to incorrect boundary conditions in the Graphics: WebGPU component when rendering content. A remote attacker can supply crafted content to disclose sensitive information.
How to mitigate CVE-2026-12303
Install security update from vendor's website.