CVE-2026-50695

Windows Active Directory Federation Services Denial of Service Vulnerability

Published Jul 14, 2026 CVSS 3.1 · 7.5 High EPSS 1.2% KEV · Not listed

Description

Stack-based buffer overflow in Active Directory Federation Services allows an unauthorized attacker to deny service over a network.

Analysis

Technical impact

The vulnerability is a stack-based buffer overflow in Windows Active Directory Federation Services (AD FS). An attacker can send a malformed federation request that corrupts a stack buffer, allowing the service to terminate or restart, resulting in a denial of service that disables AD FS functionality. This flaw is categorized as CWE‑121.

Affected Systems

Affected Windows operating systems include Windows 10 versions 1607, 1809, 21H2, and 22H2, Windows 11 versions 24H2, 25H2, and 26H1, and Windows Server releases 2012, 2012 R2, 2016, 2019, 2022, and 2025, both normal and Server Core installations, across x86, x64 and arm64 architectures.

Risk and Exploitability

The CVSS score of 7.5 indicates moderate‑to‑high severity with medium complexity and a sole impact on AD FS availability. EPSS is less than 1 %, suggesting a low current exploitation probability, and the issue is not listed in CISA’s KEV catalog. The attack vector is inferred to be remote, requiring an attacker able to send specially crafted federation requests over the network to trigger the overflow.

Affected Products

Default status is the baseline for the product, each version can override it (e.g. patched versions marked unaffected).

Vendor Product Default status Versions

Microsoft

Windows 10 Version 1607

affected

Version	Status	Constraints
`10.0.14393.0`	affected	< 10.0.14393.9339

Microsoft

Windows 10 Version 1809

affected

Version	Status	Constraints
`10.0.17763.0`	affected	< 10.0.17763.9020

Microsoft

Windows 10 Version 21H2

affected

Version	Status	Constraints
`10.0.19044.0`	affected	< 10.0.19044.7548

Microsoft

Windows 10 Version 22H2

affected

Version	Status	Constraints
`10.0.19045.0`	affected	< 10.0.19045.7548

Microsoft

Windows 11 Version 24H2

affected

Version	Status	Constraints
`10.0.26100.0`	affected	< 10.0.26100.8875

Microsoft

Windows 11 Version 25H2

affected

Version	Status	Constraints
`10.0.26200.0`	affected	< 10.0.26200.8875

Microsoft

Windows 11 version 26H1

affected

Version	Status	Constraints
`10.0.28000.0`	affected	< 10.0.28000.2525

Microsoft

Windows Server 2012

affected

Version	Status	Constraints
`6.2.9200.0`	affected	< 6.2.9200.26226

Microsoft

Windows Server 2012 (Server Core installation)

affected

Version	Status	Constraints
`6.2.9200.0`	affected	< 6.2.9200.26226

Microsoft

Windows Server 2012 R2

affected

Version	Status	Constraints
`6.3.9600.0`	affected	< 6.3.9600.23291

Microsoft

Windows Server 2012 R2 (Server Core installation)

affected

Version	Status	Constraints
`6.3.9600.0`	affected	< 6.3.9600.23291

Microsoft

Windows Server 2016

affected

Version	Status	Constraints
`10.0.14393.0`	affected	< 10.0.14393.9339

Microsoft

Windows Server 2016 (Server Core installation)

affected

Version	Status	Constraints
`10.0.14393.0`	affected	< 10.0.14393.9339

Microsoft

Windows Server 2019

affected

Version	Status	Constraints
`10.0.17763.0`	affected	< 10.0.17763.9020

Microsoft

Windows Server 2019 (Server Core installation)

affected

Version	Status	Constraints
`10.0.17763.0`	affected	< 10.0.17763.9020

Microsoft

Windows Server 2022

affected

Version	Status	Constraints
`10.0.20348.0`	affected	< 10.0.20348.5386

Microsoft

Windows Server 2025

affected

Version	Status	Constraints
`10.0.26100.0`	affected	< 10.0.26100.33158

Microsoft

Windows Server 2025 (Server Core installation)

affected

Version	Status	Constraints
`10.0.26100.0`	affected	< 10.0.26100.33158

Configuration 1 [-]

OR	cpe:2.3:o:microsoft:windows_10_1607:::::::x64:*
	cpe:2.3:o:microsoft:windows_10_1607:::::::x86:*
	cpe:2.3:o:microsoft:windows_10_1809:::::::x64:*
	cpe:2.3:o:microsoft:windows_10_1809:::::::x86:*
	cpe:2.3:o:microsoft:windows_10_21h2:::::::arm64:*
	cpe:2.3:o:microsoft:windows_10_21h2:::::::x64:*
	cpe:2.3:o:microsoft:windows_10_21h2:::::::x86:*
	cpe:2.3:o:microsoft:windows_10_22h2:::::::arm64:*
	cpe:2.3:o:microsoft:windows_10_22h2:::::::x64:*
	cpe:2.3:o:microsoft:windows_10_22h2:::::::x86:*
	cpe:2.3:o:microsoft:windows_11_24h2:::::::arm64:*
	cpe:2.3:o:microsoft:windows_11_24h2:::::::x64:*
	cpe:2.3:o:microsoft:windows_11_25h2:::::::arm64:*
	cpe:2.3:o:microsoft:windows_11_25h2:::::::x64:*
	cpe:2.3:o:microsoft:windows_11_26h1:::::::x64:*
	cpe:2.3:o:microsoft:windows_11_26h1:::::::arm64:*
	cpe:2.3:o:microsoft:windows_server_2012:-:::::::*
	cpe:2.3:o:microsoft:windows_server_2012:r2:::::::*
	cpe:2.3:o:microsoft:windows_server_2016::::::::
	cpe:2.3:o:microsoft:windows_server_2019::::::::
	cpe:2.3:o:microsoft:windows_server_2022::::::::
	cpe:2.3:o:microsoft:windows_server_2025::::::::

No data.

Vendor Product Versions

Microsoft

Windows 10 1607

Version	Status	Scheme	Platform
`[10.0.14393.0,10.0.14393.9339)`	affected	generic	['32-bit_systems', 'x64-based_systems']

Microsoft

Windows 10 1809

Version	Status	Scheme	Platform
`[10.0.17763.0,10.0.17763.9020)`	affected	generic	['32-bit_systems', 'x64-based_systems']

Microsoft

Windows 10 21h2

Version	Status	Scheme	Platform
`[10.0.19044.0,10.0.19044.7548)`	affected	generic	['32-bit_systems', 'x64-based_systems']

Microsoft

Windows 10 22h2

Version	Status	Scheme	Platform
`[10.0.19045.0,10.0.19045.7548)`	affected	generic	['32-bit_systems', 'x64-based_systems']

Microsoft

Windows 11 24h2

Version	Status	Scheme	Platform
`[10.0.26100.0,10.0.26100.8875)`	affected	generic	['arm64-based_systems', 'x64-based_systems']

Microsoft

Windows 11 25h2

Version	Status	Scheme	Platform
`[10.0.26200.0,10.0.26200.8875)`	affected	generic	['arm64-based_systems', 'x64-based_systems']

Microsoft

Windows 11 26h1

Version	Status	Scheme	Platform
`[10.0.28000.0,10.0.28000.2525)`	affected	generic	['arm64-based_systems', 'x64-based_systems']

Microsoft

Windows Server 2012

Version	Status	Scheme	Platform
`[6.2.9200.0,6.2.9200.26226)`	affected	generic	['x64-based_systems']

Microsoft

Windows Server 2012 (server Core Installation)

Version	Status	Scheme	Platform
`[6.2.9200.0,6.2.9200.26226)`	affected	generic	['x64-based_systems']

Microsoft

Windows Server 2012 R2

Version	Status	Scheme	Platform
`[6.3.9600.0,6.3.9600.23291)`	affected	generic	['x64-based_systems']

Microsoft

Windows Server 2012 R2 (server Core Installation)

Version	Status	Scheme	Platform
`[6.3.9600.0,6.3.9600.23291)`	affected	generic	['x64-based_systems']

Microsoft

Windows Server 2016

Version	Status	Scheme	Platform
`[10.0.14393.0,10.0.14393.9339)`	affected	generic	['x64-based_systems']

Microsoft

Windows Server 2016 (server Core Installation)

Version	Status	Scheme	Platform
`[10.0.14393.0,10.0.14393.9339)`	affected	generic	['x64-based_systems']

Microsoft

Windows Server 2019

Version	Status	Scheme	Platform
`[10.0.17763.0,10.0.17763.9020)`	affected	generic	['x64-based_systems']

Microsoft

Windows Server 2019 (server Core Installation)

Version	Status	Scheme	Platform
`[10.0.17763.0,10.0.17763.9020)`	affected	generic	['x64-based_systems']

Microsoft

Windows Server 2022

Version	Status	Scheme	Platform
`[10.0.20348.0,10.0.20348.5386)`	affected	generic	['x64-based_systems']

Microsoft

Windows Server 2025

Version	Status	Scheme	Platform
`[10.0.26100.0,10.0.26100.33158)`	affected	generic	['x64-based_systems']

Microsoft

Windows Server 2025 (server Core Installation)

Version	Status	Scheme	Platform
`[10.0.26100.0,10.0.26100.33158)`	affected	generic	['x64-based_systems']

Remediation

No solution or workaround provided in the CVE record.

OpenCVE Recommended Actions

Download and install the Microsoft security update for CVE‑2026‑50695 from the Microsoft Security Response Center update guide
If the AD FS role is not required for your environment, uninstall or disable it to remove the vulnerable code path
Configure firewalls and monitor logs for abnormal AD FS traffic, and block repeated failure patterns that could indicate attempts to trigger the buffer overflow

Generated by OpenCVE AI on July 31, 2026 at 09:37 UTC.

Tracking

Advisories

No advisories available

Metrics

No CVSS v4.0

Attack Vector Network

Attack Complexity Low

Privileges Required None

Scope Unchanged

Confidentiality Impact None

Integrity Impact None

Availability Impact High

User Interaction None

No CVSS v3.0

No CVSS v2

This CVE is not in the KEV list.

Exploit prediction score: 1.2% (1.174% probability within 30 days)

Exploitation none

Automatable yes

Technical Impact partial

References

Link	Providers
https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-50695

History

Nov 11, 2026 1:30 AM First appearance in the feed. Affected vendors updated View changes

Type	Values Removed	Values Added
First Time appeared		Microsoft windows Server 2012 (server Core Installation) Microsoft windows Server 2012 R2 Microsoft windows Server 2012 R2 (server Core Installation) Microsoft windows Server 2016 (server Core Installation) Microsoft windows Server 2019 (server Core Installation) Microsoft windows Server 2025 (server Core Installation)
Vendors & Products		Microsoft windows Server 2012 (server Core Installation) Microsoft windows Server 2012 R2 Microsoft windows Server 2012 R2 (server Core Installation) Microsoft windows Server 2016 (server Core Installation) Microsoft windows Server 2019 (server Core Installation) Microsoft windows Server 2025 (server Core Installation)

Jul 14, 2026 10:30 PM Scoring metrics updated View changes

Type	Values Removed	Values Added
Metrics		ssvc `{'options': {'Automatable': 'yes', 'Exploitation': 'none', 'Technical Impact': 'partial'}, 'version': '2.0.3'}`

Jul 14, 2026 5:15 PM Description updated. Title updated. First appearance in the feed. Weaknesses updated. Affected versions updated. Affected vendors updated. Added references. Scoring metrics updated View changes

Type	Values Removed	Values Added
Description		Stack-based buffer overflow in Active Directory Federation Services allows an unauthorized attacker to deny service over a network.
Title		Windows Active Directory Federation Services Denial of Service Vulnerability
First Time appeared		Microsoft Microsoft windows 10 1607 Microsoft windows 10 1809 Microsoft windows 10 21h2 Microsoft windows 10 22h2 Microsoft windows 11 24h2 Microsoft windows 11 25h2 Microsoft windows 11 26h1 Microsoft windows Server 2012 Microsoft windows Server 2012 R2 Microsoft windows Server 2016 Microsoft windows Server 2019 Microsoft windows Server 2022 Microsoft windows Server 2025
Weaknesses		CWE-121
CPEs		cpe:2.3:o:microsoft:windows_10_1607:::::::x86:* cpe:2.3:o:microsoft:windows_10_1809:::::::x86:* cpe:2.3:o:microsoft:windows_10_21H2:::::::x86:* cpe:2.3:o:microsoft:windows_10_22H2:::::::x64:* cpe:2.3:o:microsoft:windows_11_24H2:::::::arm64:* cpe:2.3:o:microsoft:windows_11_25H2:::::::arm64:* cpe:2.3:o:microsoft:windows_11_26H1:::::::x64:* cpe:2.3:o:microsoft:windows_server_2012:::::::x64:* cpe:2.3:o:microsoft:windows_server_2012_R2:::::::x64:* cpe:2.3:o:microsoft:windows_server_2016:::::::: cpe:2.3:o:microsoft:windows_server_2019:::::::: cpe:2.3:o:microsoft:windows_server_2022:::::::: cpe:2.3:o:microsoft:windows_server_2025::::::::
Vendors & Products		Microsoft Microsoft windows 10 1607 Microsoft windows 10 1809 Microsoft windows 10 21h2 Microsoft windows 10 22h2 Microsoft windows 11 24h2 Microsoft windows 11 25h2 Microsoft windows 11 26h1 Microsoft windows Server 2012 Microsoft windows Server 2012 R2 Microsoft windows Server 2016 Microsoft windows Server 2019 Microsoft windows Server 2022 Microsoft windows Server 2025
References		https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-50695
Metrics		cvssV3_1 `{'score': 7.5, 'vector': 'CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H/E:U/RL:O/RC:C'}`

Subscriptions

Microsoft Windows 10 1607 Windows 10 1809 Windows 10 21h2 Windows 10 21h2 Windows 10 22h2 Windows 10 22h2 Windows 11 24h2 Windows 11 24h2 Windows 11 25h2 Windows 11 25h2 Windows 11 26h1 Windows 11 26h1 Windows Server 2012 Windows Server 2012 (server Core Installation) Windows Server 2012 R2 Windows Server 2012 R2 Windows Server 2012 R2 (server Core Installation) Windows Server 2016 Windows Server 2016 (server Core Installation) Windows Server 2019 Windows Server 2019 (server Core Installation) Windows Server 2022 Windows Server 2025 Windows Server 2025 (server Core Installation)

Weaknesses