---
id: CVE-2026-50684
title: Active Directory Federation Server Spoofing Vulnerability
summary: >-
  Improper neutralization of input during web page generation ('cross-site
  scripting') in Active Directory Federation Services (AD FS) allows an
  authorized attacker to perform spoofing over a network.
severity: medium
cvss: 4.8
cvssVector: 'CVSS:3.1/AV:N/AC:L/PR:H/UI:R/S:C/C:L/I:L/A:N/E:U/RL:O/RC:C'
cvssSource: cna
cwe:
  - CWE-79
vendor: Microsoft
product: Windows 10 Version 1607
affected:
  - windows_10_version_1607 >= 10.0.14393.0 < 10.0.14393.9339
  - windows_10_version_1809 >= 10.0.17763.0 < 10.0.17763.9020
  - windows_server_2012 >= 6.2.9200.0 < 6.2.9200.26226
  - windows_server_2012_server_core_installation >= 6.2.9200.0 < 6.2.9200.26226
  - windows_server_2012_r2 >= 6.3.9600.0 < 6.3.9600.23291
  - >-
    windows_server_2012_r2_server_core_installation >= 6.3.9600.0 <
    6.3.9600.23291
  - windows_server_2016 >= 10.0.14393.0 < 10.0.14393.9339
  - >-
    windows_server_2016_server_core_installation >= 10.0.14393.0 <
    10.0.14393.9339
  - windows_server_2019 >= 10.0.17763.0 < 10.0.17763.9020
  - >-
    windows_server_2019_server_core_installation >= 10.0.17763.0 <
    10.0.17763.9020
  - windows_server_2022 >= 10.0.20348.0 < 10.0.20348.5386
  - windows_server_2025 >= 10.0.26100.0 < 10.0.26100.33158
  - >-
    windows_server_2025_server_core_installation >= 10.0.26100.0 <
    10.0.26100.33158
ssvc:
  exploitation: none
  automatable: 'no'
  technicalImpact: partial
  timestamp: '2026-07-14T19:12:10.573430Z'
published: '2026-07-14'
updated: '2026-09-17'
sourceUpdated: '2026-09-17T22:32:17.053Z'
source: CVEORG
sourceUrl: 'https://www.cve.org/CVERecord?id=CVE-2026-50684'
references:
  - url: 'https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-50684'
    label: Active Directory Federation Server Spoofing Vulnerability
tags:
  - cve.org
epss: 0.00395
epssPercentile: 0.33594
ingestedAt: '2026-09-08T17:06:31.912Z'
---

## Overview

Improper neutralization of input during web page generation ('cross-site scripting') in Active Directory Federation Services (AD FS) allows an authorized attacker to perform spoofing over a network.

## Affected

- `windows_10_version_1607 >= 10.0.14393.0 < 10.0.14393.9339`
- `windows_10_version_1809 >= 10.0.17763.0 < 10.0.17763.9020`
- `windows_server_2012 >= 6.2.9200.0 < 6.2.9200.26226`
- `windows_server_2012_server_core_installation >= 6.2.9200.0 < 6.2.9200.26226`
- `windows_server_2012_r2 >= 6.3.9600.0 < 6.3.9600.23291`
- `windows_server_2012_r2_server_core_installation >= 6.3.9600.0 < 6.3.9600.23291`
- `windows_server_2016 >= 10.0.14393.0 < 10.0.14393.9339`
- `windows_server_2016_server_core_installation >= 10.0.14393.0 < 10.0.14393.9339`
- `windows_server_2019 >= 10.0.17763.0 < 10.0.17763.9020`
- `windows_server_2019_server_core_installation >= 10.0.17763.0 < 10.0.17763.9020`
- `windows_server_2022 >= 10.0.20348.0 < 10.0.20348.5386`
- `windows_server_2025 >= 10.0.26100.0 < 10.0.26100.33158`
- `windows_server_2025_server_core_installation >= 10.0.26100.0 < 10.0.26100.33158`

## Remediation

Refer to the linked advisories for vendor-supplied fixes and affected version ranges.