Denial of Service Vulnerability in Active Directory Federation Services by Microsoft
CVE-2026-50647

7.5HIGH

Key Information:

Vendor

Microsoft
Status
Microsoft .net Framework 3.5 And 4.7.2
Microsoft .net Framework 3.5 And 4.8
Microsoft .net Framework 3.5 And 4.8.1
Microsoft .net Framework 4.6.2/4.7/4.7.1/4.7.2
Vendor
CVE Published:
14 July 2026

What is CVE-2026-50647?

A vulnerability exists in Active Directory Federation Services (AD FS) that causes an endless loop with an unreachable exit condition. This flaw may allow unauthorized attackers to exploit the system, leading to service disruptions over a network, preventing legitimate users from accessing essential services.

Affected Version(s)

Microsoft .NET Framework 3.5 AND 4.7.2 Windows 10 Version 1607 for 32-bit Systems 4.7.0 < 2.0.50727.9069 & 3.0.30729.9067 & 4.7.4143.0

Microsoft .NET Framework 3.5 AND 4.8 Windows 10 Version 1809 for 32-bit Systems 4.8.0 < 2.0.50727.9069 & 3.0.30729.9067 & 4.8.4803.0

Microsoft .NET Framework 3.5 AND 4.8.1 Windows 10 Version 21H2 for 32-bit Systems 4.8.1 < 2.0.50727.9182 & 3.0.30729.9168 & 4.8.9339.0

References

https://msrc.microsoft.com/update-guide/vulnerability/CVE...
vendor-advisorypatch

CVSS V3.1

Score:
7.5
Severity:
HIGH
Confidentiality:
None
Integrity:
None
Availability:
None
Attack Vector:
Network
Attack Complexity:
Low
Privileges Required:
None
User Interaction:
None
Scope:
Unchanged

Timeline

  • Vulnerability published

  • Vulnerability Reserved

.