Input validation error in Windows Server - CVE-2026-26154
Published: April 14, 2026
Vulnerability identifier: #VU126008
CSH Severity: Medium
CVSS v4: 8.7 [CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N]
CVE-ID: CVE-2026-26154
CWE-ID: CWE-20
Exploitation vector: Remote access
Exploit availability:
No public exploit available
Vulnerability details
The vulnerability allows a remote attacker to perform a denial of service (DoS) attack.
The vulnerability exists due to insufficient validation of user-supplied input in Windows Server Update Service (WSUS). A remote attacker can pass specially crafted input to the application and perform a denial of service (DoS) attack.
Affected software
Windows Server
How to mitigate CVE-2026-26154
Install updates from vendor's website.
Windows Server - addressed in versions 2012 R2 6.3.9600.23132, 2012 6.2.9200.26026, 2016 10.0.14393.9060, 2019 10.0.17763.8644, 2022 23H2 10.0.25398.2274, 2022 10.0.20348.5020, 2025 10.0.26100.32690