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"vendor": "microsoft"}, {"configurations": [{"platform": ["x64-based_systems"], "status": "affected", "versions": {"scheme": "generic", "value": "[10.0.26100.0,10.0.26100.32690)"}}], "enrichment": {"confidence": 100.0, "confidence_source": "matching", "scores": [{"score": 100.0, "source": "matching"}]}, "original": {"product": "Windows Server 2025 (Server Core installation)", "source": "cna", "vendor": "Microsoft"}, "product": "windows_server_2025_(server_core_installation)", "vendor": "microsoft"}], "analysis": {"en": {"generated_at": "2026-04-14T20:10:12.226384+00:00", "value": {"mitigation_remediation": ["Apply the official Microsoft security update for this vulnerability from the Microsoft Security Update Guide or Update Catalog.", "Verify the patch has been installed by reviewing the WSUS service version or the Windows Update history.", "Restrict external access to the WSUS server using firewall rules or network segmentation, allowing only trusted administrators to communicate with it."], "summary": {"action": "Immediate Patch", "impact": "Unauthorized WSUS Tampering"}, "threat_synthesis": {"affected_systems": "Affected are Microsoft Windows Server 2012, 2012\u202fR2, 2016, 2019, 2022, 2025, and 23H2, including both standard and Server Core installations. These versions are listed in the CNA affected\u2011products list and cover all 64\u2011bit editions of the operating system.", "description_and_impact": "The vulnerability lies in incorrect input validation within the Windows Server Update Service. An unauthorized attacker who can reach the service over a network may send specially crafted requests that allow tampering with the service\u2019s behavior. The specific effects are limited to the integrity and operation of the update distribution system, as the attacker can modify WSUS state or configuration through the service.", "risk_and_exploitability": "The CVSS score of 7.5 indicates high severity, while no EPSS data is available and the vulnerability is not listed in the KEV catalog, suggesting no widespread exploitation yet. Because the flaw is exploitable over the network and requires no authentication, any host with WSUS enabled and exposed can be targeted. This poses a significant risk to the integrity and availability of the update infrastructure in affected environments."}}}}, "created": "2026-04-15T14:31:56.925777+00:00", "updated": "2026-04-15T15:15:06.647092+00:00", "vendors": ["microsoft", "microsoft$PRODUCT$windows_server_2012", "microsoft$PRODUCT$windows_server_2012_(server_core_installation)", "microsoft$PRODUCT$windows_server_2012_r2", "microsoft$PRODUCT$windows_server_2012_r2_(server_core_installation)", "microsoft$PRODUCT$windows_server_2016", "microsoft$PRODUCT$windows_server_2016_(server_core_installation)", "microsoft$PRODUCT$windows_server_2019", "microsoft$PRODUCT$windows_server_2019_(server_core_installation)", "microsoft$PRODUCT$windows_server_2022", "microsoft$PRODUCT$windows_server_2022,_23h2_edition_(server_core_installation)", "microsoft$PRODUCT$windows_server_2025", "microsoft$PRODUCT$windows_server_2025_(server_core_installation)"]}