Incorrect authorization in Microsoft Windows and Windows Server - CVE-2026-69640
Published: October 13, 2026
Vulnerability identifier: #VU154406
CSH Severity: Low
CVSS v4: 6 [CVSS:4.0/AV:N/AC:L/AT:P/PR:L/UI:N/VC:H/VI:N/VA:N/SC:N/SI:N/SA:N]
CVE-ID: CVE-2026-69640
CWE-ID: CWE-863
Exploitation vector: Remote access
Exploit availability:
No public exploit available
Vulnerability details
The vulnerability allows a remote user to bypass Kerberos service ticketing access control checks.
The vulnerability exists due to incorrect authorization in Windows Key Distribution Center when performing user access control checks for Kerberos service ticketing. A remote user can exploit the authorization flaw over a network to bypass Kerberos service ticketing access control checks.
Successful exploitation requires specific protocol settings or configurations to be in place. No user interaction is required.
Affected software
Microsoft Windows
Windows Server
Windows Server
How to mitigate CVE-2026-69640
Install security update from vendor's website.
Microsoft Windows - addressed in versions 10 1607 10.0.14393.9612, 10 1809 10.0.17763.9376, 11 24H2 10.0.26100.9711, 11 25H2 10.0.26200.9711, 11 26H1 10.0.28000.3231
Windows Server - addressed in versions 2012 R2 6.3.9600.23470, 2012 6.2.9200.26434, 2016 10.0.14393.9612, 2019 10.0.17763.9376, 2022 10.0.20348.5761, 2025 10.0.26100.33650
Windows Server - addressed in versions 2012 R2 6.3.9600.23470, 2012 6.2.9200.26434, 2016 10.0.14393.9612, 2019 10.0.17763.9376, 2022 10.0.20348.5761, 2025 10.0.26100.33650