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TI-2021-17505 Aliases CVE-2021-40456GHSA-j5xg-6v4g-89vw

Windows AD FS Security Feature Bypass Vulnerability

Priority MEDIUM 43CWE-863Published · Updated

Key facts

Attack vector
Network
Privileges required
None
User interaction
None
Attack complexity
Low
Impact type
Security bypass
Confidentiality · integrity · availability
High · None · None
Fix status
Fixed

Attack profile from CVSS 3.1 · NVD. Fix status from CNA. Impact type from CWE-863.

Summary

Windows AD FS Security Feature Bypass Vulnerability

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.02341 83rd percentileScored 2026-11-07
Fix Fixed Windows Server 2019 (Microsoft): 10.0.17763.2237Windows Server 2019 (Server Core installation) (Microsoft): 10.0.17763.2237+3 more products

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation
None
Automatable
Yes
Technical impact
Partial

The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.

Affected products

VendorProductAffected versionsFixed inStatusSource
MicrosoftWindows Server 201910.0.0 to before 10.0.17763.223710.0.17763.2237Patch availableCNA
MicrosoftWindows Server 2019 (Server Core installation)10.0.0 to before 10.0.17763.223710.0.17763.2237Patch availableCNA
MicrosoftWindows Server 202210.0.0 to before 10.0.20348.28810.0.20348.288Patch availableCNA
MicrosoftWindows Server version 200410.0.0 to before 10.0.19041.128810.0.19041.1288Patch availableCNA
MicrosoftWindows Server version 20H210.0.0 to before 10.0.19042.128810.0.19042.1288Patch availableCNA
  • Windows Server 2019 VendorMicrosoft Affected 10.0.0 to before 10.0.17763.2237 Fixed in 10.0.17763.2237 Patch available CNA
  • Windows Server 2019 (Server Core installation) VendorMicrosoft Affected 10.0.0 to before 10.0.17763.2237 Fixed in 10.0.17763.2237 Patch available CNA
  • Windows Server 2022 VendorMicrosoft Affected 10.0.0 to before 10.0.20348.288 Fixed in 10.0.20348.288 Patch available CNA
  • Windows Server version 2004 VendorMicrosoft Affected 10.0.0 to before 10.0.19041.1288 Fixed in 10.0.19041.1288 Patch available CNA
  • Windows Server version 20H2 VendorMicrosoft Affected 10.0.0 to before 10.0.19042.1288 Fixed in 10.0.19042.1288 Patch available CNA

CPE configurations NVD · 3

CPEVersionsRoleVendor
cpe:2.3:o:microsoft:windows_server:20h2:*:*:*:*:*:*:*20h2VulnerableMicrosoft
cpe:2.3:o:microsoft:windows_server_2019:-:*:*:*:*:*:*:*not specified by NVDVulnerableMicrosoft
cpe:2.3:o:microsoft:windows_server_2022:*:*:*:*:*:*:*:*all versionsVulnerableMicrosoft
  • cpe:2.3:o:microsoft:windows_server:20h2:*:*:*:*:*:*:* Versions 20h2 Vulnerable ·Microsoft
  • cpe:2.3:o:microsoft:windows_server_2019:-:*:*:*:*:*:*:* Versions not specified by NVD Vulnerable ·Microsoft
  • cpe:2.3:o:microsoft:windows_server_2022:*:*:*:*:*:*:*:* Versions all versions Vulnerable ·Microsoft

Remediation

  • Fix · CNA Windows Server 2019 (Microsoft) Fixed in 10.0.17763.2237
  • Fix · CNA Windows Server 2019 (Server Core installation) (Microsoft) Fixed in 10.0.17763.2237
  • Fix · CNA Windows Server 2022 (Microsoft) Fixed in 10.0.20348.288
  • Fix · CNA Windows Server version 2004 (Microsoft) Fixed in 10.0.19041.1288
  • Fix · CNA Windows Server version 20H2 (Microsoft) Fixed in 10.0.19042.1288

Timeline

  1. 2026-10-02 Threatist record created from CVE-2021-40456
  2. 2026-10-03 Alias added: GHSA-j5xg-6v4g-89vw

References

Patch 1

  • TI-2022-06273 HTTP Protocol Stack Remote Code Execution Vulnerability CVSS 3.1CRITICAL 9.8
  • TI-2022-10168 Windows Network File System Remote Code Execution Vulnerability CVSS 3.1CRITICAL 9.8
  • TI-2022-06260 Secure Boot Security Feature Bypass Vulnerability CVSS 3.1MEDIUM 4.4
  • TI-2022-06331 Windows Point-to-Point Tunneling Protocol Remote Code Execution Vulnerability CVSS 3.1HIGH 8.1
  • TI-2022-07395 Windows Point-to-Point Tunneling Protocol Remote Code Execution Vulnerability CVSS 3.1HIGH 8.1
  • TI-2022-06206 Windows Certificate Spoofing Vulnerability CVSS 3.1HIGH 7.8
See all 272 →

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences