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TI-2026-72161 Aliases CVE-2026-70056GHSA-6qxr-4mv2-mhx8

Windows Update Service Elevation of Privilege Vulnerability

Priority LOW 33CWE-416Published · Updated

Key facts

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

Attack profile from CVSS 3.1 · CNA. Fix status from CNA and Microsoft. Impact type from Microsoft.

Summary

Use after free (CWE-416) in Windows Update Service allows an authorized attacker to gain higher privileges locally. The CVSS 3.1 base score is 7.0 (HIGH). Microsoft rates exploitation as less likely, reports no public disclosure or exploitation, and CISA's KEV catalog does not list the vulnerability.

Written with Claude Haiku 5.5 from the sources below · 2026-10-27

Description from the CNA

Use after free in Windows Update Service allows an authorized attacker to elevate privileges locally.

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.003 22nd percentileScored 2026-11-07
Fix Fixed Microsoft: 7 updates

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation
None
Automatable
No
Technical impact
Total

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 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 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 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 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 · 21

CPEVersionsRoleVendor
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_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_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
  • 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
Show 11 more CPE
CPEVersionsRoleVendor
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_2019:*:*:*:*:*:*:*:*before 10.0.17763.9376VulnerableMicrosoft
cpe:2.3:o:microsoft:windows_server_2022:*:*:*:*:*:*:x64:*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_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_2019:*:*:*:*:*:*:*:* Versions before 10.0.17763.9376 Vulnerable ·Microsoft
  • cpe:2.3:o:microsoft:windows_server_2022:*:*:*:*:*:*:x64:* 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

Install the Microsoft security update for your edition: KB5126646 for Windows Server 2025, KB5126651 for Windows 10 1809 and Windows Server 2019, KB5126655 for Windows Server 2022, and KB5126657 for Windows 10 21H2 and 22H2. The fixed builds are 10.0.17763.9376 (Windows 10 1809 and Server 2019), 10.0.19044.7807 (21H2), 10.0.19045.7807 (22H2), 10.0.20348.5761 (Server 2022), 10.0.22631.7652 (23H2), 10.0.26100.9711 (24H2), 10.0.26200.9711 (25H2), 10.0.26300.9711 (26H2), 10.0.28000.3231 (26H1) and 10.0.26100.33650 (Server 2025).

Written with Claude Haiku 5.5 from the sources below · 2026-10-27

Microsoft 7 updates

  • Security Update
    • Windows 11 Version 24H2 for ARM64-based Systems 10.0.26100.9711
    • Windows 11 Version 24H2 for x64-based Systems 10.0.26100.9711
    • Windows 11 Version 25H2 for ARM64-based Systems 10.0.26200.9711
    • Windows 11 Version 25H2 for x64-based Systems 10.0.26200.9711
    • Windows 11 Version 26H2 for ARM64-based Systems 10.0.26300.9711
    • Windows 11 Version 26H2 for x64-based Systems 10.0.26300.9711
  • Security Update
    • Windows 11 Version 26H1 for ARM64-based Systems 10.0.28000.3231
    • Windows 11 version 26H1 for x64-based Systems 10.0.28000.3231
  • Security Update
    • Windows 10 Version 21H2 for 32-bit Systems 10.0.19044.7807
    • Windows 10 Version 21H2 for ARM64-based Systems 10.0.19044.7807
    • Windows 10 Version 21H2 for x64-based Systems 10.0.19044.7807
    • Windows 10 Version 22H2 for 32-bit Systems 10.0.19044.7807, 10.0.19045.7807
    • Windows 10 Version 22H2 for ARM64-based Systems 10.0.19044.7807, 10.0.19045.7807
    • Windows 10 Version 22H2 for x64-based Systems 10.0.19044.7807, 10.0.19045.7807
Show 4 more Microsoft updates
  • Security Update
    • Windows Server 2022 10.0.20348.5761
    • Windows Server 2022 (Server Core installation) 10.0.20348.5761
  • Security Update
    • Windows 11 Version 23H2 for ARM64-based Systems 10.0.22631.7652
    • Windows 11 Version 23H2 for x64-based Systems 10.0.22631.7652
  • Security Update
    • Windows 10 Version 1809 for 32-bit Systems 10.0.17763.9376
    • Windows 10 Version 1809 for x64-based Systems 10.0.17763.9376
    • Windows Server 2019 10.0.17763.9376
    • Windows Server 2019 (Server Core installation) 10.0.17763.9376
  • Security Update
    • Windows Server 2025 10.0.26100.33650
    • Windows Server 2025 (Server Core installation) 10.0.26100.33650

Vendor assessments

Microsoft

Microsoft's page for this CVE →

Impact
Elevation of Privilege
Exploited
No
Publicly disclosed
No
Exploitability
Exploitation Less Likely

Timeline

  1. 2026-10-13 Threatist record created from CVE-2026-70056
  2. 2026-10-13 Alias added: GHSA-6qxr-4mv2-mhx8
  3. 2026-10-13 CISA SSVC decision points changed
  4. 2026-10-14 Priority changed: MEDIUM → LOW
  5. 2026-10-14 CISA SSVC decision points changed
  6. 2026-10-16 Fix available: KB5126646, KB5126651, KB5126653 +4 · Microsoft
  7. 2026-10-16 Fix available: Microsoft/Windows 10 Version [email protected] · CNA

References

  • TI-2026-26194 Windows Internet Key Exchange (IKE) Service Extensions Remote Code Execution Vulnerability 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
  • TI-2025-24042 Internet Shortcut Files Remote Code Execution Vulnerability KEVCVSS 3.1HIGH 8.8
See all 4016 →

Sources