Log in Start free

Vulnerability · Published Apr 14, 2026 · Assigned by microsoft

CVE-2026-26154Windows Server Update Service (WSUS) Tampering Vulnerability

High 7.5

In plain English

A high-severity improper input validation in Windows Server 2012 from Microsoft. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 1.1% (higher than 65% of all known vulnerabilities).

Severity (CVSS 3.1)7.5High
Exploit odds (30 days)1.1%top 35.2% of all CVEs
Exploited in the wildNo reportsCISA SSVC: none
Attack toolingNoneno public tooling known

Official description

Improper input validation in Windows Server Update Service allows an unauthorized attacker to perform tampering over a network.

Affected products (as reported)

VendorProductVersions
Microsoft Windows Server 2012 6.2.9200.0 – before 6.2.9200.26026
Microsoft Windows Server 2012 (Server Core installation) 6.2.9200.0 – before 6.2.9200.26026
Microsoft Windows Server 2012 R2 6.3.9600.0 – before 6.3.9600.23132
Microsoft Windows Server 2012 R2 (Server Core installation) 6.3.9600.0 – before 6.3.9600.23132
Microsoft Windows Server 2016 10.0.14393.0 – before 10.0.14393.9060
Microsoft Windows Server 2016 (Server Core installation) 10.0.14393.0 – before 10.0.14393.9060
Microsoft Windows Server 2019 10.0.17763.0 – before 10.0.17763.8644
Microsoft Windows Server 2019 (Server Core installation) 10.0.17763.0 – before 10.0.17763.8644
Microsoft Windows Server 2022 10.0.20348.0 – before 10.0.20348.5020
Microsoft Windows Server 2022, 23H2 Edition (Server Core installation) 10.0.25398.0 – before 10.0.25398.2274
Microsoft Windows Server 2025 10.0.26100.0 – before 10.0.26100.32690
Microsoft Windows Server 2025 (Server Core installation) 10.0.26100.0 – before 10.0.26100.32690

Weakness: CWE-20 · Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H/E:U/RL:O/RC:C

References