CVE-2025-21311: Windows NTLM V1 Elevation of Privilege Vulnerability

Overview

Severity

Critical (CVSS 9.8)

CVSS Vector

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

Category

Elevation of Privilege

Exploit Status

Not Exploited

Exploitation Likelihood

Less Likely

Patch Tuesday

2025-Jan

Released

2025-01-14

EPSS Score

3.28% (percentile: 87.2%)

FAQ

According to the CVSS metric, the attack vector is network (AV:N) and the attack complexity is low (AC:L). What does that mean for this vulnerability? The attack vector is Network (AV:N) because this vulnerability is remotely exploitable and can be exploited from the internet. The attack complexity is Low (AC:L) because an attacker does not require significant prior knowledge of the system and can achieve repeatable success with the payload against the vulnerable component.

Affected Products (5)

Windows

• Windows Server 2025 (Server Core installation)
• Windows Server 2022, 23H2 Edition (Server Core installation)
• Windows 11 Version 24H2 for ARM64-based Systems
• Windows 11 Version 24H2 for x64-based Systems
• Windows Server 2025

Security Updates (2)

• 5050009
• 5049984

Acknowledgments

Dylan Bickerstaff with <a href="https://belowaverage.org/">below average</a>

Revision History

• 2025-01-14: Information published.