What is CVE-2025-11719?

CVE-2025-11719 is a critical-severity vulnerability in Microsoft Windows, classified under Use After Free. CVSS score: 9.8/10. Published 2025-10-14.

How severe is CVE-2025-11719?

Critical severity. CVSS v3 base score is 9.8 out of 10.

Use After Free in Microsoft Windows

CVE-2025-11719

Starting in Thunderbird 143, the use of the native messaging API by web extensions on Windows could lead to crashes caused by use-after-free memory corruption. This vulnerability was fixed in Firefox 144 and Thunderbird 144.

Vulnerability class: Use-After-Free

EPSS: 0.003 (24.0th percentile) — read the EPSS interpretation.

CVSS v3 metric

CVSS v3 base score 9.8 (Critical). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H.

Affected products

Microsoft Windows
Mozilla Firefox — versions 144
Mozilla Thunderbird — versions 144

Weakness classification (CWE)

CWE-416 — Use After Free

References

security@mozilla.org (Permissions Required, Issue Tracking)
security@mozilla.org (Vendor Advisory)
security@mozilla.org (Vendor Advisory)

Frequently asked questions

What is CVE-2025-11719?: CVE-2025-11719 is a critical-severity vulnerability in Microsoft Windows, classified under Use After Free. CVSS score: 9.8/10. Published 2025-10-14.
How severe is CVE-2025-11719?: Critical severity. CVSS v3 base score is 9.8 out of 10.