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

Published Jul 14, 2026
·
Updated

Active Directory Federation Server Denial of Service Vulnerability

Other sources

Loop with unreachable exit condition ('infinite loop') in Active Directory Federation Services (AD FS) allows an unauthorized attacker to deny service over a network.

— Microsoft

Affected Software

118 affected componentsFixes available
Microsoft Windows Server 2022<10.0.20348.5386
10.0.20348.5386
Microsoft Windows Server 2025<10.0.26100.33158
10.0.26100.33158
Microsoft Windows 10=22H2
10.0.19045.7548
Microsoft Windows 10=22H2
10.0.19045.7548
Microsoft Windows 10=21H2
10.0.19044.7548
Microsoft Windows 10=22H2
10.0.19045.7548
Microsoft Windows 10=21H2
10.0.19044.7548
Microsoft Windows Server 2012 R2<6.3.9600.23291
6.3.9600.23291
Microsoft Windows Server 2012<6.2.9200.26226
6.2.9200.26226
Microsoft Windows 10=21H2
10.0.19044.7548
Microsoft Windows 10=1607
10.0.14393.9339
Microsoft Windows Server 2016<10.0.14393.9339
10.0.14393.9339
Microsoft Windows Server 2016<10.0.14393.9339
10.0.14393.9339
Microsoft Windows 11=26H1
10.0.28000.2525
Microsoft Windows 10=1607
10.0.14393.9339
Microsoft Windows 11=26H1
10.0.28000.2525
Microsoft Windows 11=24H2
10.0.26100.8875
Microsoft Windows Server 2012<6.2.9200.26226
6.2.9200.26226
Microsoft Windows Server 2012 R2<6.3.9600.23291
6.3.9600.23291
Microsoft Windows Server 2019<10.0.17763.9020
10.0.17763.9020
Microsoft Windows 10=1809
10.0.17763.9020
Microsoft Windows Server 2019<10.0.17763.9020
10.0.17763.9020
Microsoft Windows Server 2025<10.0.26100.33158
10.0.26100.33158
Microsoft Windows 11=24H2
10.0.26100.8875
Microsoft Windows 10=1809
10.0.17763.9020
Microsoft .NET Framework=3.5, =4.8.1
2.0.50727.9182 & 3.0.30729.9168
Microsoft .NET Framework=3.5
2.0.50727.8983 & 3.0.30729.8978
Microsoft .NET Framework=3.5, =4.8.1
2.0.50727.9182 & 3.0.30729.9168 & 4.8.9340.0
Microsoft .NET Framework=3.5, =4.8.1
2.0.50727.9182 & 3.0.30729.9168 & 4.8.9339.0
Microsoft .NET Framework=3.5
2.0.50727.8983 & 3.0.30729.8978
Microsoft .NET Framework=3.5, =4.8.1
2.0.50727.9182 & 3.0.30729.9168 & 4.8.9339.0
Microsoft .NET Framework=3.5, =4.8.1
2.0.50727.9182 & 3.0.30729.9168 & 4.8.9340.0
Microsoft .NET Framework=3.5, =4.8.1
2.0.50727.9182 & 3.0.30729.9168 & 4.8.9339.0
Microsoft .NET Framework=4.6.2, =4.7, =4.7.1, =4.7.2
4.7.4143.0
Microsoft .NET Framework=3.5, =4.7.2
2.0.50727.8983 & 3.0.30729.8978 & 4.7.4143.0
Microsoft .NET Framework=4.6.2, =4.7, =4.7.1, =4.7.2
4.7.4143.0
Microsoft .NET Framework=3.5, =4.7.2
2.0.50727.9069 & 3.0.30729.9067 & 4.7.4143.0
Microsoft .NET Framework=3.5, =4.8
2.0.50727.9182 & 3.0.30729.9168 & 4.8.4803.0
Microsoft .NET Framework=3.5, =4.8
2.0.50727.9182 & 3.0.30729.9168 & 4.8.4803.0
Microsoft .NET Framework=3.5, =4.8
2.0.50727.9069 & 3.0.30729.9067 & 4.8.4803.0
Microsoft .NET Framework=4.8
4.8.4803.0
Microsoft .NET Framework=4.8
4.8.4803.0
Microsoft .NET Framework=4.8
4.8.4803.0
Microsoft .NET Framework=4.8.1
4.8.9340.0
Microsoft Windows 11=25H2
10.0.26200.8875
Microsoft Windows 11=25H2
10.0.26200.8875
Microsoft Windows 10 1607<10.0.14393.9339
Microsoft Windows 10 1607<10.0.14393.9339
Microsoft Windows 10 1809<10.0.17763.9020
Microsoft Windows 10 1809<10.0.17763.9020
Microsoft Windows 10 21h2<10.0.19044.7548
Microsoft Windows 10 21h2<10.0.19044.7548
Microsoft Windows 10 21h2<10.0.19044.7548
Microsoft Windows 10 22h2<10.0.19045.7548
Microsoft Windows 10 22h2<10.0.19045.7548
Microsoft Windows 10 22h2<10.0.19045.7548
Microsoft Windows 11 24h2<10.0.26100.8875
Microsoft Windows 11 24h2<10.0.26100.8875
Microsoft Windows 11 25h2<10.0.26200.8875
Microsoft Windows 11 25h2<10.0.26200.8875
Microsoft Windows 11 26h1<10.0.28000.2525
Microsoft Windows 11 26h1<10.0.28000.2525
Microsoft Windows Server 2012
Microsoft Windows Server 2012=r2
Microsoft Windows Server 2016<10.0.14393.9339
Microsoft Windows Server 2019<10.0.17763.9020
Microsoft Windows Server 2022<10.0.20348.5386
Microsoft Windows Server 2025<10.0.26100.33158
All of the following
Microsoft .NET Framework=4.8.1
Any of the following
Microsoft Windows 11 26h1
Microsoft Windows 11 26h1
All of the following
Microsoft .NET Framework=4.8
Any of the following
Microsoft Windows 10 1607
Microsoft Windows 10 1607
Microsoft Windows Server 2012
Microsoft Windows Server 2012=r2
Microsoft Windows Server 2016
All of the following
Any of the following
Microsoft .NET Framework=4.6.2
Microsoft .NET Framework=4.7
Microsoft .NET Framework=4.7.1
Microsoft .NET Framework=4.7.2
Any of the following
Microsoft Windows Server 2012
Microsoft Windows Server 2012=r2
All of the following
Any of the following
Microsoft .NET Framework=3.5
Microsoft .NET Framework=4.8.1
Any of the following
Microsoft Windows 10 21h2
Microsoft Windows 10 21h2
Microsoft Windows 10 21h2
Microsoft Windows 10 22h2
Microsoft Windows 10 22h2
Microsoft Windows 10 22h2
Microsoft Windows 11 23h2
Microsoft Windows 11 23h2
Microsoft Windows 11 24h2
Microsoft Windows 11 24h2
Microsoft Windows 11 25h2
Microsoft Windows 11 25h2
Microsoft Windows Server 2022
All of the following
Any of the following
Microsoft .NET Framework=3.5
Microsoft .NET Framework=4.8
Any of the following
Microsoft Windows 10 1809
Microsoft Windows 10 1809
Microsoft Windows 10 21h2
Microsoft Windows 10 21h2
Microsoft Windows 10 21h2
Microsoft Windows 10 22h2
Microsoft Windows 10 22h2
Microsoft Windows 10 22h2
Microsoft Windows Server 2019
Microsoft Windows Server 2022
All of the following
Any of the following
Microsoft .NET Framework=3.5
Microsoft .NET Framework=4.7.2
Any of the following
Microsoft Windows 10 1607
Microsoft Windows 10 1607
Microsoft Windows 10 1809
Microsoft Windows 10 1809
Microsoft Windows Server 2016
Microsoft Windows Server 2019

Remediation

Patch Available

https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-50647

Event History

Jul 14, 2026
CVE Published
via Microsoft·02:00 PM
Data Sourced
via Microsoft·02:00 PM
DescriptionSeverityWeaknessAffected Software
Updated
via Microsoft·02:00 PM
Affected Software
Updated
via Microsoft·02:00 PM
Description
CVE Published
via MITRE·05:08 PM
Data Sourced
via MITRE·05:08 PM
DescriptionSeverity
Data Sourced
via NVD·06:17 PM
RemedyDescriptionSeverityWeaknessAffected Software

Frequently Asked Questions

1

What is the severity of CVE-2026-50647?

CVE-2026-50647 has a severity rating of 7.5, classified as high.

2

How do I fix CVE-2026-50647?

To mitigate CVE-2026-50647, ensure your Active Directory Federation Services are updated with the latest patches from Microsoft.

3

What does CVE-2026-50647 affect?

CVE-2026-50647 affects various Microsoft products, including Microsoft .NET Framework, Windows 10, Windows 11, and multiple versions of Windows Server.

4

What type of vulnerability is CVE-2026-50647?

CVE-2026-50647 is a denial of service vulnerability that can cause an infinite loop in Active Directory Federation Services.

5

How can CVE-2026-50647 be exploited?

CVE-2026-50647 can be exploited by an unauthorized attacker to deny service over a network.

Company

Resources

Contact

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