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TI-2026-72568 Aliases CVE-2026-83798GHSA-fjm3-5v9c-74p5

Spoofing in Windows Update Stack from improper signature verification

Priority LOW 24CWE-20Published · Updated

Key facts

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

Attack profile from CVSS 3.1 · CNA. Fix status from CNA. Impact type from CWE-347.

Summary

Microsoft Windows Update Stack in Windows 10 Version 1607, Windows 10 Version 1809, Windows 10 Version 21H2, Windows 10 Version 22H2, Windows 11 version 23H2 and other products is affected. Improper verification of a cryptographic signature (CWE-347) lets updates be spoofed. A local attacker with low privileges can spoof updates without any user interaction.

Written with Claude Haiku 5.5 from the sources below · 2026-10-28

Description from the CNA

Improper verification of cryptographic signature in Windows Update Stack allows an authorized attacker to perform spoofing locally.

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.00239 15th percentileScored 2026-11-07
Fix Fixed Windows 10 Version 1607 (Microsoft): 10.0.14393.9612Windows 10 Version 1809 (Microsoft): 10.0.17763.9376+19 more products

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation
None
Automatable
No
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 10 Version 160710.0.14393.0 to before 10.0.14393.961210.0.14393.9612Patch availableCNA
MicrosoftWindows 10 Version 180910.0.17763.0 to before 10.0.17763.937610.0.17763.9376Patch availableCNA
MicrosoftWindows 10 Version 21H210.0.19044.0 to before 10.0.19044.780710.0.19044.7807Patch availableCNA
MicrosoftWindows 10 Version 22H210.0.19045.0 to before 10.0.19045.780710.0.19045.7807Patch availableCNA
MicrosoftWindows 11 version 23H210.0.22631.0 to before 10.0.22631.765210.0.22631.7652Patch availableCNA
MicrosoftWindows 11 Version 23H210.0.22631.0 to before 10.0.22631.765210.0.22631.7652Patch availableCNA
MicrosoftWindows 11 Version 24H210.0.26100.0 to before 10.0.26100.971110.0.26100.9711Patch availableCNA
MicrosoftWindows 11 Version 25H210.0.26200.0 to before 10.0.26200.971110.0.26200.9711Patch availableCNA
MicrosoftWindows 11 version 26H110.0.28000.0 to before 10.0.28000.323110.0.28000.3231Patch availableCNA
MicrosoftWindows 11 Version 26H210.0.26300.0 to before 10.0.26300.971110.0.26300.9711Patch availableCNA
MicrosoftWindows Server 20126.2.9200.0 to before 6.2.9200.264346.2.9200.26434Patch availableCNA
MicrosoftWindows Server 2012 (Server Core installation)6.2.9200.0 to before 6.2.9200.264346.2.9200.26434Patch availableCNA
MicrosoftWindows Server 2012 R26.3.9600.0 to before 6.3.9600.234706.3.9600.23470Patch availableCNA
MicrosoftWindows Server 2012 R2 (Server Core installation)6.3.9600.0 to before 6.3.9600.234706.3.9600.23470Patch availableCNA
MicrosoftWindows Server 201610.0.14393.0 to before 10.0.14393.961210.0.14393.9612Patch availableCNA
MicrosoftWindows Server 2016 (Server Core installation)10.0.14393.0 to before 10.0.14393.961210.0.14393.9612Patch availableCNA
MicrosoftWindows Server 201910.0.17763.0 to before 10.0.17763.937610.0.17763.9376Patch availableCNA
MicrosoftWindows Server 2019 (Server Core installation)10.0.17763.0 to before 10.0.17763.937610.0.17763.9376Patch availableCNA
MicrosoftWindows Server 202210.0.20348.0 to before 10.0.20348.576110.0.20348.5761Patch availableCNA
MicrosoftWindows Server 202510.0.26100.0 to before 10.0.26100.3365010.0.26100.33650Patch availableCNA
MicrosoftWindows Server 2025 (Server Core installation)10.0.26100.0 to before 10.0.26100.3365010.0.26100.33650Patch availableCNA
  • Windows 10 Version 1607 VendorMicrosoft Affected 10.0.14393.0 to before 10.0.14393.9612 Fixed in 10.0.14393.9612 Patch available CNA
  • Windows 10 Version 1809 VendorMicrosoft Affected 10.0.17763.0 to before 10.0.17763.9376 Fixed in 10.0.17763.9376 Patch available CNA
  • Windows 10 Version 21H2 VendorMicrosoft Affected 10.0.19044.0 to before 10.0.19044.7807 Fixed in 10.0.19044.7807 Patch available CNA
  • Windows 10 Version 22H2 VendorMicrosoft Affected 10.0.19045.0 to before 10.0.19045.7807 Fixed in 10.0.19045.7807 Patch available CNA
  • Windows 11 version 23H2 VendorMicrosoft Affected 10.0.22631.0 to before 10.0.22631.7652 Fixed in 10.0.22631.7652 Patch available CNA
  • Windows 11 Version 23H2 VendorMicrosoft Affected 10.0.22631.0 to before 10.0.22631.7652 Fixed in 10.0.22631.7652 Patch available CNA
  • Windows 11 Version 24H2 VendorMicrosoft Affected 10.0.26100.0 to before 10.0.26100.9711 Fixed in 10.0.26100.9711 Patch available CNA
  • Windows 11 Version 25H2 VendorMicrosoft Affected 10.0.26200.0 to before 10.0.26200.9711 Fixed in 10.0.26200.9711 Patch available CNA
  • Windows 11 version 26H1 VendorMicrosoft Affected 10.0.28000.0 to before 10.0.28000.3231 Fixed in 10.0.28000.3231 Patch available CNA
  • Windows 11 Version 26H2 VendorMicrosoft Affected 10.0.26300.0 to before 10.0.26300.9711 Fixed in 10.0.26300.9711 Patch available CNA
  • Windows Server 2012 VendorMicrosoft Affected 6.2.9200.0 to before 6.2.9200.26434 Fixed in 6.2.9200.26434 Patch available CNA
  • Windows Server 2012 (Server Core installation) VendorMicrosoft Affected 6.2.9200.0 to before 6.2.9200.26434 Fixed in 6.2.9200.26434 Patch available CNA
  • Windows Server 2012 R2 VendorMicrosoft Affected 6.3.9600.0 to before 6.3.9600.23470 Fixed in 6.3.9600.23470 Patch available CNA
  • Windows Server 2012 R2 (Server Core installation) VendorMicrosoft Affected 6.3.9600.0 to before 6.3.9600.23470 Fixed in 6.3.9600.23470 Patch available CNA
  • Windows Server 2016 VendorMicrosoft Affected 10.0.14393.0 to before 10.0.14393.9612 Fixed in 10.0.14393.9612 Patch available CNA
  • Windows Server 2016 (Server Core installation) VendorMicrosoft Affected 10.0.14393.0 to before 10.0.14393.9612 Fixed in 10.0.14393.9612 Patch available CNA
  • Windows Server 2019 VendorMicrosoft Affected 10.0.17763.0 to before 10.0.17763.9376 Fixed in 10.0.17763.9376 Patch available CNA
  • Windows Server 2019 (Server Core installation) VendorMicrosoft Affected 10.0.17763.0 to before 10.0.17763.9376 Fixed in 10.0.17763.9376 Patch available CNA
  • Windows Server 2022 VendorMicrosoft Affected 10.0.20348.0 to before 10.0.20348.5761 Fixed in 10.0.20348.5761 Patch available CNA
  • Windows Server 2025 VendorMicrosoft Affected 10.0.26100.0 to before 10.0.26100.33650 Fixed in 10.0.26100.33650 Patch available CNA
  • Windows Server 2025 (Server Core installation) VendorMicrosoft Affected 10.0.26100.0 to before 10.0.26100.33650 Fixed in 10.0.26100.33650 Patch available CNA

CPE configurations NVD · 26

CPEVersionsRoleVendor
cpe:2.3:o:microsoft:windows_10_1607:*:*:*:*:*:*:x64:*before 10.0.14393.9612VulnerableMicrosoft
cpe:2.3:o:microsoft:windows_10_1607:*:*:*:*:*:*:x86:*before 10.0.14393.9612VulnerableMicrosoft
cpe:2.3:o:microsoft:windows_10_1809:*:*:*:*:*:*:x64:*before 10.0.17763.9376VulnerableMicrosoft
cpe:2.3:o:microsoft:windows_10_1809:*:*:*:*:*:*:x86:*before 10.0.17763.9376VulnerableMicrosoft
cpe:2.3:o:microsoft:windows_10_21h2:*:*:*:*:*:*:arm64:*before 10.0.19044.7807VulnerableMicrosoft
cpe:2.3:o:microsoft:windows_10_21h2:*:*:*:*:*:*:x64:*before 10.0.19044.7807VulnerableMicrosoft
cpe:2.3:o:microsoft:windows_10_21h2:*:*:*:*:*:*:x86:*before 10.0.19044.7807VulnerableMicrosoft
cpe:2.3:o:microsoft:windows_10_22h2:*:*:*:*:*:*:arm64:*before 10.0.19045.7807VulnerableMicrosoft
cpe:2.3:o:microsoft:windows_10_22h2:*:*:*:*:*:*:x64:*before 10.0.19045.7807VulnerableMicrosoft
cpe:2.3:o:microsoft:windows_10_22h2:*:*:*:*:*:*:x86:*before 10.0.19045.7807VulnerableMicrosoft
  • cpe:2.3:o:microsoft:windows_10_1607:*:*:*:*:*:*:x64:* Versions before 10.0.14393.9612 Vulnerable ·Microsoft
  • cpe:2.3:o:microsoft:windows_10_1607:*:*:*:*:*:*:x86:* Versions before 10.0.14393.9612 Vulnerable ·Microsoft
  • cpe:2.3:o:microsoft:windows_10_1809:*:*:*:*:*:*:x64:* Versions before 10.0.17763.9376 Vulnerable ·Microsoft
  • cpe:2.3:o:microsoft:windows_10_1809:*:*:*:*:*:*:x86:* Versions before 10.0.17763.9376 Vulnerable ·Microsoft
  • cpe:2.3:o:microsoft:windows_10_21h2:*:*:*:*:*:*:arm64:* Versions before 10.0.19044.7807 Vulnerable ·Microsoft
  • cpe:2.3:o:microsoft:windows_10_21h2:*:*:*:*:*:*:x64:* Versions before 10.0.19044.7807 Vulnerable ·Microsoft
  • cpe:2.3:o:microsoft:windows_10_21h2:*:*:*:*:*:*:x86:* Versions before 10.0.19044.7807 Vulnerable ·Microsoft
  • cpe:2.3:o:microsoft:windows_10_22h2:*:*:*:*:*:*:arm64:* Versions before 10.0.19045.7807 Vulnerable ·Microsoft
  • cpe:2.3:o:microsoft:windows_10_22h2:*:*:*:*:*:*:x64:* Versions before 10.0.19045.7807 Vulnerable ·Microsoft
  • cpe:2.3:o:microsoft:windows_10_22h2:*:*:*:*:*:*:x86:* Versions before 10.0.19045.7807 Vulnerable ·Microsoft
Show 16 more CPE
CPEVersionsRoleVendor
cpe:2.3:o:microsoft:windows_11_23h2:*:*:*:*:*:*:arm64:*before 10.0.22631.7652VulnerableMicrosoft
cpe:2.3:o:microsoft:windows_11_23h2:*:*:*:*:*:*:x64:*before 10.0.22631.7652VulnerableMicrosoft
cpe:2.3:o:microsoft:windows_11_24h2:*:*:*:*:*:*:arm64:*before 10.0.26100.9711VulnerableMicrosoft
cpe:2.3:o:microsoft:windows_11_24h2:*:*:*:*:*:*:x64:*before 10.0.26100.9711VulnerableMicrosoft
cpe:2.3:o:microsoft:windows_11_25h2:*:*:*:*:*:*:arm64:*before 10.0.26200.9711VulnerableMicrosoft
cpe:2.3:o:microsoft:windows_11_25h2:*:*:*:*:*:*:x64:*before 10.0.26200.9711VulnerableMicrosoft
cpe:2.3:o:microsoft:windows_11_26h1:*:*:*:*:*:*:arm64:*before 10.0.28000.3231VulnerableMicrosoft
cpe:2.3:o:microsoft:windows_11_26h1:*:*:*:*:*:*:x64:*before 10.0.28000.3231VulnerableMicrosoft
cpe:2.3:o:microsoft:windows_11_26h2:*:*:*:*:*:*:arm64:*before 10.0.26300.9711VulnerableMicrosoft
cpe:2.3:o:microsoft:windows_11_26h2:*:*:*:*:*:*:x64:*before 10.0.26300.9711VulnerableMicrosoft
cpe:2.3:o:microsoft:windows_server_2012:-:*:*:*:*:*:*:*not specified by NVDVulnerableMicrosoft
cpe:2.3:o:microsoft:windows_server_2012:r2:*:*:*:*:*:*:*r2VulnerableMicrosoft
cpe:2.3:o:microsoft:windows_server_2016:*:*:*:*:*:*:*:*before 10.0.14393.9612VulnerableMicrosoft
cpe:2.3:o:microsoft:windows_server_2019:*:*:*:*:*:*:*:*before 10.0.17763.9376VulnerableMicrosoft
cpe:2.3:o:microsoft:windows_server_2022:*:*:*:*:*:*:*:*before 10.0.20348.5761VulnerableMicrosoft
cpe:2.3:o:microsoft:windows_server_2025:*:*:*:*:*:*:x64:*before 10.0.26100.33650VulnerableMicrosoft
  • cpe:2.3:o:microsoft:windows_11_23h2:*:*:*:*:*:*:arm64:* Versions before 10.0.22631.7652 Vulnerable ·Microsoft
  • cpe:2.3:o:microsoft:windows_11_23h2:*:*:*:*:*:*:x64:* Versions before 10.0.22631.7652 Vulnerable ·Microsoft
  • cpe:2.3:o:microsoft:windows_11_24h2:*:*:*:*:*:*:arm64:* Versions before 10.0.26100.9711 Vulnerable ·Microsoft
  • cpe:2.3:o:microsoft:windows_11_24h2:*:*:*:*:*:*:x64:* Versions before 10.0.26100.9711 Vulnerable ·Microsoft
  • cpe:2.3:o:microsoft:windows_11_25h2:*:*:*:*:*:*:arm64:* Versions before 10.0.26200.9711 Vulnerable ·Microsoft
  • cpe:2.3:o:microsoft:windows_11_25h2:*:*:*:*:*:*:x64:* Versions before 10.0.26200.9711 Vulnerable ·Microsoft
  • cpe:2.3:o:microsoft:windows_11_26h1:*:*:*:*:*:*:arm64:* Versions before 10.0.28000.3231 Vulnerable ·Microsoft
  • cpe:2.3:o:microsoft:windows_11_26h1:*:*:*:*:*:*:x64:* Versions before 10.0.28000.3231 Vulnerable ·Microsoft
  • cpe:2.3:o:microsoft:windows_11_26h2:*:*:*:*:*:*:arm64:* Versions before 10.0.26300.9711 Vulnerable ·Microsoft
  • cpe:2.3:o:microsoft:windows_11_26h2:*:*:*:*:*:*:x64:* Versions before 10.0.26300.9711 Vulnerable ·Microsoft
  • cpe:2.3:o:microsoft:windows_server_2012:-:*:*:*:*:*:*:* Versions not specified by NVD Vulnerable ·Microsoft
  • cpe:2.3:o:microsoft:windows_server_2012:r2:*:*:*:*:*:*:* Versions r2 Vulnerable ·Microsoft
  • cpe:2.3:o:microsoft:windows_server_2016:*:*:*:*:*:*:*:* Versions before 10.0.14393.9612 Vulnerable ·Microsoft
  • cpe:2.3:o:microsoft:windows_server_2019:*:*:*:*:*:*:*:* Versions before 10.0.17763.9376 Vulnerable ·Microsoft
  • cpe:2.3:o:microsoft:windows_server_2022:*:*:*:*:*:*:*:* Versions before 10.0.20348.5761 Vulnerable ·Microsoft
  • cpe:2.3:o:microsoft:windows_server_2025:*:*:*:*:*:*:x64:* Versions before 10.0.26100.33650 Vulnerable ·Microsoft

Remediation

Fixed versions are 10.0.14393.9612 for Windows 10 Version 1607 and Windows Server 2016, 10.0.17763.9376 for Windows 10 Version 1809, 10.0.19044.7807 for Windows 10 Version 21H2, 10.0.19045.7807 for Windows 10 Version 22H2, 10.0.22631.7652 for Windows 11 Version 23H2, 10.0.26100.9711 for Windows 11 Version 24H2, 6.2.9200.26434 for Windows Server 2012, and 6.3.9600.23470 for Windows Server 2012 R2.

Written with Claude Haiku 5.5 from the sources below · 2026-10-28

  • Fix · CNA Windows 10 Version 1607 (Microsoft) Fixed in 10.0.14393.9612
  • Fix · CNA Windows 10 Version 1809 (Microsoft) Fixed in 10.0.17763.9376
  • Fix · CNA Windows 10 Version 21H2 (Microsoft) Fixed in 10.0.19044.7807
  • Fix · CNA Windows 10 Version 22H2 (Microsoft) Fixed in 10.0.19045.7807
  • Fix · CNA Windows 11 version 23H2 (Microsoft) Fixed in 10.0.22631.7652
  • Fix · CNA Windows 11 Version 23H2 (Microsoft) Fixed in 10.0.22631.7652
  • Fix · CNA Windows 11 Version 24H2 (Microsoft) Fixed in 10.0.26100.9711
  • Fix · CNA Windows 11 Version 25H2 (Microsoft) Fixed in 10.0.26200.9711
  • Fix · CNA Windows 11 version 26H1 (Microsoft) Fixed in 10.0.28000.3231
  • Fix · CNA Windows 11 Version 26H2 (Microsoft) Fixed in 10.0.26300.9711
  • Fix · CNA Windows Server 2012 (Microsoft) Fixed in 6.2.9200.26434
  • Fix · CNA Windows Server 2012 (Server Core installation) (Microsoft) Fixed in 6.2.9200.26434
  • Fix · CNA Windows Server 2012 R2 (Microsoft) Fixed in 6.3.9600.23470
  • Fix · CNA Windows Server 2012 R2 (Server Core installation) (Microsoft) Fixed in 6.3.9600.23470
  • Fix · CNA Windows Server 2016 (Microsoft) Fixed in 10.0.14393.9612
  • Fix · CNA Windows Server 2016 (Server Core installation) (Microsoft) Fixed in 10.0.14393.9612
  • Fix · CNA Windows Server 2019 (Microsoft) Fixed in 10.0.17763.9376
  • Fix · CNA Windows Server 2019 (Server Core installation) (Microsoft) Fixed in 10.0.17763.9376
  • Fix · CNA Windows Server 2022 (Microsoft) Fixed in 10.0.20348.5761
  • Fix · CNA Windows Server 2025 (Microsoft) Fixed in 10.0.26100.33650
  • Fix · CNA Windows Server 2025 (Server Core installation) (Microsoft) Fixed in 10.0.26100.33650

Timeline

  1. 2026-10-13 Threatist record created from CVE-2026-83798
  2. 2026-10-13 Alias added: GHSA-fjm3-5v9c-74p5
  3. 2026-10-14 Priority changed: MEDIUM → LOW
  4. 2026-10-15 CISA SSVC decision points changed
  5. 2026-10-16 Fix available: Microsoft/Windows 10 Version [email protected] · CNA

References

Patch 1

  • TI-2026-26194 Windows Internet Key Exchange (IKE) Service Extensions Remote Code Execution Vulnerability KEVCVSS 3.1CRITICAL 9.8
  • TI-2017-06077 Microsoft Windows XP SP3, Windows XP x64 XP2, Windows Server 2003 SP2, Windows Vista… KEVCVSS 3.1CRITICAL 9.8
  • TI-2026-73128 Windows Shell Security Feature Bypass Vulnerability KEVCVSS 3.1HIGH 8.8
  • TI-2026-17367 MSHTML Framework Security Feature Bypass Vulnerability KEVCVSS 3.1HIGH 8.8
  • TI-2026-17364 Windows Shell Security Feature Bypass Vulnerability KEVCVSS 3.1HIGH 8.8
  • TI-2025-24062 Windows SMB Client Elevation of Privilege Vulnerability KEVCVSS 3.1HIGH 8.8
See all 3427 →

Sources

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