Description
Improper input validation in Windows Server Update Service allows an unauthorized attacker to perform tampering over a network.
Affected products
microsoft: windows server 2012; microsoft: windows server 2016; microsoft: windows server 2019; microsoft: windows server 2022; microsoft: windows server 2022 23h2; microsoft: windows server 2025
References1
- msrc.microsoft.com/update-guide/vulnerability/CVE-2026-26154 Vendor Advisory
Metrics
- CVSS 3.1
-
7.5
HIGH
Score source: CNA
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H - EPSS — exploit probability
- 1% percentile: 66 · as of 12 November 2026
- CWE
- CWE-20
Could this be exploited in your environment?
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