CVE-2026-12289

Privilege escalation in the Graphics: WebRender component. This vulnerability was fixed in Firefox 152, Firefox ESR 140.12, Firefox ESR 115.37, Thunderbird 152, and Thunderbird 140.12.

CVSS 3.1

8.8CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H

EPSS

0.4% chance of exploitation in the next 30 days; higher than 33% of CVEs (scores of 2026-10-25)

CWEs

CWE-269, CWE-266

Published

2026-06-16

Modified

2026-10-26

Record from

the NVD, synced 2026-10-26

Affected

• mozilla:firefox
• mozilla:thunderbird

References

• https://bugzilla.mozilla.org/show_bug.cgi?id=2023443
• https://www.mozilla.org/security/advisories/mfsa2026-57/
• https://www.mozilla.org/security/advisories/mfsa2026-58/
• https://www.mozilla.org/security/advisories/mfsa2026-59/
• https://www.mozilla.org/security/advisories/mfsa2026-60/

Check your stackJSON