CVE-2026-27912: Windows Kerberos Elevation of Privilege Vulnerability

Overview

Severity

High (CVSS 8)

CVSS Vector

CVSS:3.1/AV:A/AC:L/PR:L/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

2026-Apr

Released

2026-04-14

Description

Improper authorization in Windows Kerberos allows an authorized attacker to elevate privileges over an adjacent network.

FAQ

According to the CVSS metric, the attack vector is adjacent (AV:A). What does that mean for this vulnerability? Successful exploitation of this vulnerability requires that an attacker needs to be in the same restricted Active Directory domain as the target system. The attack surface is not reachable from broader networks, which is why the attack vector is considered adjacent (AV:A). What privileges could be gained by an attacker who successfully exploited this vulnerability? An attacker who successfully exploited this vulnerability could gain SYSTEM privileges.

Affected Products (13)

Windows

• Windows Server 2019
• Windows Server 2019 (Server Core installation)
• Windows Server 2022
• Windows Server 2022 (Server Core installation)
• Windows Server 2025 (Server Core installation)
• Windows Server 2022, 23H2 Edition (Server Core installation)
• Windows Server 2025
• Windows Server 2016
• Windows Server 2016 (Server Core installation)

ESU

• Windows Server 2012
• Windows Server 2012 (Server Core installation)
• Windows Server 2012 R2
• Windows Server 2012 R2 (Server Core installation)

Security Updates (7)

• 5082123
• 5082142
• 5082063
• 5082060
• 5082198
• 5082127
• 5082126

Acknowledgments

<a href="https://www.linkedin.com/in/shailaron">Shai Laron</a> with Semperis

Revision History

• 2026-04-14: Information published.