CVE-2025-21311

Name: CVE-2025-21311
Creator: NVD / NIST
Published: 2025-01-14T18:15:54.567+00:00
License: https://creativecommons.org/publicdomain/zero/1.0/

CRITICALCVSS 9.8/10EPSS 2.35%

Last modified Jun 17, 2026

CVE-2025-21311 is a critical-severity vulnerability rated 9.8/10 on the CVSS scale. Windows NTLM V1 Elevation of Privilege Vulnerability. EPSS estimates a 2.35% chance of exploitation in the next 30 days.

Description

Windows NTLM V1 Elevation of Privilege Vulnerability

Metrics

CVSS 3.1

9.8/10

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

EPSS Probability

2.35%

81.5th percentile

Probability of exploitation in the next 30 days. Learn more

Weakness Enumeration

CWE-303

Affected Software

Vendor	Product	Versions
Microsoft	Windows 11 24h2	< 10.0.26100.2894
Microsoft	Windows Server 2022 23h2	< 10.0.25398.1369
Microsoft	Windows Server 2025	< 10.0.26100.2894

References

https://msrc.microsoft.com/update-guide/vulnerability/CVE-2025-21311Patch, Vendor Advisory

Timeline

Published: Jan 14, 2025
Last Modified: Jun 17, 2026
Status: Analyzed

Frequently Asked Questions

What is CVE-2025-21311?

Windows NTLM V1 Elevation of Privilege Vulnerability

How severe is CVE-2025-21311?

CVE-2025-21311 has a CVSS score of 9.8/10 (CRITICAL severity). The EPSS model estimates a 2.35% probability of exploitation in the next 30 days.

How do I fix CVE-2025-21311?

Check the vendor references and advisories linked above for patched versions and mitigation guidance. You can also run a Strix scan to test if your systems are affected.

Are you affected by CVE-2025-21311?

Run a free Strix scan to check your systems for this vulnerability.

Scan your code now

Source: NVD / NIST