---
id: CVE-2026-70005
title: >-
  Weak authentication in Active Directory Federation Services (AD FS) allows an
  unauthorized attacker to bypass a security feature over a network.
summary: >-
  Weak authentication in Active Directory Federation Services (AD FS) allows an
  unauthorized attacker to bypass a security feature over a network.
severity: medium
cvss: 5.9
cvssVector: 'CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:H/A:N'
cwe:
  - CWE-1390
published: '2026-10-13'
updated: '2026-10-14'
sourceUpdated: '2026-10-14T19:17:19.407'
source: NVD
sourceUrl: 'https://nvd.nist.gov/vuln/detail/CVE-2026-70005'
references:
  - url: 'https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-70005'
    label: secure@microsoft.com
tags:
  - nvd
  - cve.org
epss: 0.00642
epssPercentile: 0.50565
ingestedAt: '2026-10-13T19:43:28.981Z'
vendor: Microsoft
product: Windows Server 2019
affected:
  - windows_server_2019 >= 10.0.17763.0 < 10.0.17763.9376
  - >-
    windows_server_2019_server_core_installation >= 10.0.17763.0 <
    10.0.17763.9376
  - windows_server_2022 >= 10.0.20348.0 < 10.0.20348.5761
  - windows_server_2025 >= 10.0.26100.0 < 10.0.26100.33650
  - >-
    windows_server_2025_server_core_installation >= 10.0.26100.0 <
    10.0.26100.33650
ssvc:
  exploitation: none
  automatable: 'no'
  technicalImpact: partial
  timestamp: '2026-10-14T18:46:52.300405Z'
---

## Overview

Weak authentication in Active Directory Federation Services (AD FS) allows an unauthorized attacker to bypass a security feature over a network.

## Remediation

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