Windows CVE-2026-20856
HIGHCVSS VectorNVD
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H
Lifecycle Timeline
2DescriptionNVD
Improper input validation in Windows Server Update Service allows an unauthorized attacker to execute code over a network.
AnalysisAI
Remote code execution in Windows Server Update Service affects Windows 11 25h2, Windows Server 2025, 2022, and 2016 due to inadequate input validation, enabling unauthenticated network-based attackers to execute arbitrary code with high impact. The vulnerability requires specific conditions to exploit (high complexity) but carries significant risk across widely-deployed server infrastructure with no patch currently available.
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RemediationAI
Within 7 days: Identify all affected systems and apply vendor patches promptly. Monitor vendor channels for patch availability.
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