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HIGH Vulnerabilities Microsoft Security Response Center

CVE-2026-50647 Active Directory Federation Server Denial of Service Vulnerability

A denial-of-service vulnerability (CVE-2026-50647, CVSS 7.5) exists in Active Directory Federation Services due to an infinite loop condition. An unauthenticated remote attacker can trigger this by sending specially crafted network packets, causing a service outage. Microsoft has released security updates to address this vulnerability; administrators should apply the patches corresponding to their AD FS versions immediately.
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