MS.Windows.Kerberos.CVE-2025-21299.Security.Bypass

Description

This indicates an attack attempt to exploit a Security Bypass vulnerability in Microsoft Windows Kerberos.
The vulnerability is due to an error when the vulnerable system handles a maliciously crafted request. A remote attacker may be able to exploit this to bypass security mechanism on vulnerable systems.

Affected Products

Windows 10 Version 1809 for 32-bit Systems
Windows 10 Version 1809 for x64-based Systems
Windows Server 2019
Windows Server 2019 (Server Core installation)
Windows Server 2022
Windows Server 2022 (Server Core installation)
Windows 10 Version 21H2 for 32-bit Systems
Windows 10 Version 21H2 for ARM64-based Systems
Windows 10 Version 21H2 for x64-based Systems
Windows 11 Version 22H2 for ARM64-based Systems
Windows 11 Version 22H2 for x64-based Systems
Windows 10 Version 22H2 for x64-based Systems
Windows 10 Version 22H2 for ARM64-based Systems
Windows 10 Version 22H2 for 32-bit Systems
Windows Server 2025 (Server Core installation)
Windows 11 Version 23H2 for ARM64-based Systems
Windows 11 Version 23H2 for x64-based Systems
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
Windows 10 for 32-bit Systems
Windows 10 for x64-based Systems
Windows 10 Version 1607 for 32-bit Systems
Windows 10 Version 1607 for x64-based Systems
Windows Server 2016
Windows Server 2016 (Server Core installation)

Impact

Security Bypass: Remote attackers can bypass security checks of vulnerable systems.

Recommended Actions

Apply the most recent upgrade or patch from the vendor.
https://msrc.microsoft.com/update-guide/vulnerability/CVE-2025-21299

References