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TI-2026-47439 Aliases CVE-2026-66799GHSA-cr27-wq5j-8m89

Windows Key Guard Elevation of Privilege Vulnerability

Priority LOW 36CWE-122Published · Updated

Key facts

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

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

Summary

Heap-based buffer overflow in Windows Key Guard allows an authorized attacker to elevate privileges locally.

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.00333 26th percentileScored 2026-11-07
Fix Fixed Red Hat: 5 advisoriesMicrosoft: 14 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 160710.0.14393.0 to before 10.0.14393.941810.0.14393.9418Patch availableCNA
MicrosoftWindows 10 Version 180910.0.17763.0 to before 10.0.17763.912110.0.17763.9121Patch availableCNA
MicrosoftWindows 10 Version 21H210.0.19044.0 to before 10.0.19044.766310.0.19044.7663Patch availableCNA
MicrosoftWindows 10 Version 22H210.0.19045.0 to before 10.0.19045.766310.0.19045.7663Patch availableCNA
MicrosoftWindows 11 version 23H210.0.22631.0 to before 10.0.22631.751710.0.22631.7517Patch availableCNA
MicrosoftWindows 11 Version 23H210.0.22631.0 to before 10.0.22631.751710.0.22631.7517Patch availableCNA
MicrosoftWindows 11 Version 24H210.0.26100.0 to before 10.0.26100.916810.0.26100.9168Patch availableCNA
MicrosoftWindows 11 Version 25H210.0.26200.0 to before 10.0.26200.916810.0.26200.9168Patch availableCNA
MicrosoftWindows 11 version 26H110.0.28000.0 to before 10.0.28000.270410.0.28000.2704Patch availableCNA
MicrosoftWindows Server 20126.2.9200.0 to before 6.2.9200.262806.2.9200.26280Patch availableCNA
MicrosoftWindows Server 2012 (Server Core installation)6.2.9200.0 to before 6.2.9200.262806.2.9200.26280Patch availableCNA
MicrosoftWindows Server 2012 R26.3.9600.0 to before 6.3.9600.233386.3.9600.23338Patch availableCNA
MicrosoftWindows Server 2012 R2 (Server Core installation)6.3.9600.0 to before 6.3.9600.233386.3.9600.23338Patch availableCNA
MicrosoftWindows Server 201610.0.14393.0 to before 10.0.14393.941810.0.14393.9418Patch availableCNA
MicrosoftWindows Server 2016 (Server Core installation)10.0.14393.0 to before 10.0.14393.941810.0.14393.9418Patch availableCNA
MicrosoftWindows Server 201910.0.17763.0 to before 10.0.17763.912110.0.17763.9121Patch availableCNA
MicrosoftWindows Server 2019 (Server Core installation)10.0.17763.0 to before 10.0.17763.912110.0.17763.9121Patch availableCNA
MicrosoftWindows Server 202210.0.20348.0 to before 10.0.20348.549910.0.20348.5499Patch availableCNA
MicrosoftWindows Server 202510.0.26100.0 to before 10.0.26100.3329610.0.26100.33296Patch availableCNA
MicrosoftWindows Server 2025 (Server Core installation)10.0.26100.0 to before 10.0.26100.3329610.0.26100.33296Patch availableCNA
  • Windows 10 Version 1607 VendorMicrosoft Affected 10.0.14393.0 to before 10.0.14393.9418 Fixed in 10.0.14393.9418 Patch available CNA
  • Windows 10 Version 1809 VendorMicrosoft Affected 10.0.17763.0 to before 10.0.17763.9121 Fixed in 10.0.17763.9121 Patch available CNA
  • Windows 10 Version 21H2 VendorMicrosoft Affected 10.0.19044.0 to before 10.0.19044.7663 Fixed in 10.0.19044.7663 Patch available CNA
  • Windows 10 Version 22H2 VendorMicrosoft Affected 10.0.19045.0 to before 10.0.19045.7663 Fixed in 10.0.19045.7663 Patch available CNA
  • Windows 11 version 23H2 VendorMicrosoft Affected 10.0.22631.0 to before 10.0.22631.7517 Fixed in 10.0.22631.7517 Patch available CNA
  • Windows 11 Version 23H2 VendorMicrosoft Affected 10.0.22631.0 to before 10.0.22631.7517 Fixed in 10.0.22631.7517 Patch available CNA
  • Windows 11 Version 24H2 VendorMicrosoft Affected 10.0.26100.0 to before 10.0.26100.9168 Fixed in 10.0.26100.9168 Patch available CNA
  • Windows 11 Version 25H2 VendorMicrosoft Affected 10.0.26200.0 to before 10.0.26200.9168 Fixed in 10.0.26200.9168 Patch available CNA
  • Windows 11 version 26H1 VendorMicrosoft Affected 10.0.28000.0 to before 10.0.28000.2704 Fixed in 10.0.28000.2704 Patch available CNA
  • Windows Server 2012 VendorMicrosoft Affected 6.2.9200.0 to before 6.2.9200.26280 Fixed in 6.2.9200.26280 Patch available CNA
  • Windows Server 2012 (Server Core installation) VendorMicrosoft Affected 6.2.9200.0 to before 6.2.9200.26280 Fixed in 6.2.9200.26280 Patch available CNA
  • Windows Server 2012 R2 VendorMicrosoft Affected 6.3.9600.0 to before 6.3.9600.23338 Fixed in 6.3.9600.23338 Patch available CNA
  • Windows Server 2012 R2 (Server Core installation) VendorMicrosoft Affected 6.3.9600.0 to before 6.3.9600.23338 Fixed in 6.3.9600.23338 Patch available CNA
  • Windows Server 2016 VendorMicrosoft Affected 10.0.14393.0 to before 10.0.14393.9418 Fixed in 10.0.14393.9418 Patch available CNA
  • Windows Server 2016 (Server Core installation) VendorMicrosoft Affected 10.0.14393.0 to before 10.0.14393.9418 Fixed in 10.0.14393.9418 Patch available CNA
  • Windows Server 2019 VendorMicrosoft Affected 10.0.17763.0 to before 10.0.17763.9121 Fixed in 10.0.17763.9121 Patch available CNA
  • Windows Server 2019 (Server Core installation) VendorMicrosoft Affected 10.0.17763.0 to before 10.0.17763.9121 Fixed in 10.0.17763.9121 Patch available CNA
  • Windows Server 2022 VendorMicrosoft Affected 10.0.20348.0 to before 10.0.20348.5499 Fixed in 10.0.20348.5499 Patch available CNA
  • Windows Server 2025 VendorMicrosoft Affected 10.0.26100.0 to before 10.0.26100.33296 Fixed in 10.0.26100.33296 Patch available CNA
  • Windows Server 2025 (Server Core installation) VendorMicrosoft Affected 10.0.26100.0 to before 10.0.26100.33296 Fixed in 10.0.26100.33296 Patch available CNA

CPE configurations NVD · 24

CPEVersionsRoleVendor
cpe:2.3:o:microsoft:windows_10_1607:*:*:*:*:*:*:x64:*before 10.0.14393.9418VulnerableMicrosoft
cpe:2.3:o:microsoft:windows_10_1607:*:*:*:*:*:*:x86:*before 10.0.14393.9418VulnerableMicrosoft
cpe:2.3:o:microsoft:windows_10_1809:*:*:*:*:*:*:x64:*before 10.0.17763.9115VulnerableMicrosoft
cpe:2.3:o:microsoft:windows_10_1809:*:*:*:*:*:*:x86:*before 10.0.17763.9115VulnerableMicrosoft
cpe:2.3:o:microsoft:windows_10_21h2:*:*:*:*:*:*:arm64:*before 10.0.19044.7663VulnerableMicrosoft
cpe:2.3:o:microsoft:windows_10_21h2:*:*:*:*:*:*:x64:*before 10.0.19044.7663VulnerableMicrosoft
cpe:2.3:o:microsoft:windows_10_21h2:*:*:*:*:*:*:x86:*before 10.0.19044.7663VulnerableMicrosoft
cpe:2.3:o:microsoft:windows_10_22h2:*:*:*:*:*:*:arm64:*before 10.0.19045.7663VulnerableMicrosoft
cpe:2.3:o:microsoft:windows_10_22h2:*:*:*:*:*:*:x64:*before 10.0.19045.7663VulnerableMicrosoft
cpe:2.3:o:microsoft:windows_10_22h2:*:*:*:*:*:*:x86:*before 10.0.19045.7663VulnerableMicrosoft
  • cpe:2.3:o:microsoft:windows_10_1607:*:*:*:*:*:*:x64:* Versions before 10.0.14393.9418 Vulnerable ·Microsoft
  • cpe:2.3:o:microsoft:windows_10_1607:*:*:*:*:*:*:x86:* Versions before 10.0.14393.9418 Vulnerable ·Microsoft
  • cpe:2.3:o:microsoft:windows_10_1809:*:*:*:*:*:*:x64:* Versions before 10.0.17763.9115 Vulnerable ·Microsoft
  • cpe:2.3:o:microsoft:windows_10_1809:*:*:*:*:*:*:x86:* Versions before 10.0.17763.9115 Vulnerable ·Microsoft
  • cpe:2.3:o:microsoft:windows_10_21h2:*:*:*:*:*:*:arm64:* Versions before 10.0.19044.7663 Vulnerable ·Microsoft
  • cpe:2.3:o:microsoft:windows_10_21h2:*:*:*:*:*:*:x64:* Versions before 10.0.19044.7663 Vulnerable ·Microsoft
  • cpe:2.3:o:microsoft:windows_10_21h2:*:*:*:*:*:*:x86:* Versions before 10.0.19044.7663 Vulnerable ·Microsoft
  • cpe:2.3:o:microsoft:windows_10_22h2:*:*:*:*:*:*:arm64:* Versions before 10.0.19045.7663 Vulnerable ·Microsoft
  • cpe:2.3:o:microsoft:windows_10_22h2:*:*:*:*:*:*:x64:* Versions before 10.0.19045.7663 Vulnerable ·Microsoft
  • cpe:2.3:o:microsoft:windows_10_22h2:*:*:*:*:*:*:x86:* Versions before 10.0.19045.7663 Vulnerable ·Microsoft
Show 14 more CPE
CPEVersionsRoleVendor
cpe:2.3:o:microsoft:windows_11_23h2:*:*:*:*:*:*:arm64:*before 10.0.22631.7517VulnerableMicrosoft
cpe:2.3:o:microsoft:windows_11_23h2:*:*:*:*:*:*:x64:*before 10.0.22631.7517VulnerableMicrosoft
cpe:2.3:o:microsoft:windows_11_24h2:*:*:*:*:*:*:arm64:*before 10.0.26100.9106VulnerableMicrosoft
cpe:2.3:o:microsoft:windows_11_24h2:*:*:*:*:*:*:x64:*before 10.0.26100.9106VulnerableMicrosoft
cpe:2.3:o:microsoft:windows_11_25h2:*:*:*:*:*:*:arm64:*before 10.0.26200.9106VulnerableMicrosoft
cpe:2.3:o:microsoft:windows_11_25h2:*:*:*:*:*:*:x64:*before 10.0.26200.9106VulnerableMicrosoft
cpe:2.3:o:microsoft:windows_11_26h1:*:*:*:*:*:*:arm64:*before 10.0.28000.2704VulnerableMicrosoft
cpe:2.3:o:microsoft:windows_11_26h1:*:*:*:*:*:*:x64:*before 10.0.28000.2704VulnerableMicrosoft
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 10.0.14393.9418VulnerableMicrosoft
cpe:2.3:o:microsoft:windows_server_2019:*:*:*:*:*:*:*:*before 10.0.17763.9115VulnerableMicrosoft
cpe:2.3:o:microsoft:windows_server_2022:*:*:*:*:*:*:*:*before 10.0.20348.5440VulnerableMicrosoft
cpe:2.3:o:microsoft:windows_server_2025:*:*:*:*:*:*:*:*before 10.0.26100.33222VulnerableMicrosoft
  • cpe:2.3:o:microsoft:windows_11_23h2:*:*:*:*:*:*:arm64:* Versions before 10.0.22631.7517 Vulnerable ·Microsoft
  • cpe:2.3:o:microsoft:windows_11_23h2:*:*:*:*:*:*:x64:* Versions before 10.0.22631.7517 Vulnerable ·Microsoft
  • cpe:2.3:o:microsoft:windows_11_24h2:*:*:*:*:*:*:arm64:* Versions before 10.0.26100.9106 Vulnerable ·Microsoft
  • cpe:2.3:o:microsoft:windows_11_24h2:*:*:*:*:*:*:x64:* Versions before 10.0.26100.9106 Vulnerable ·Microsoft
  • cpe:2.3:o:microsoft:windows_11_25h2:*:*:*:*:*:*:arm64:* Versions before 10.0.26200.9106 Vulnerable ·Microsoft
  • cpe:2.3:o:microsoft:windows_11_25h2:*:*:*:*:*:*:x64:* Versions before 10.0.26200.9106 Vulnerable ·Microsoft
  • cpe:2.3:o:microsoft:windows_11_26h1:*:*:*:*:*:*:arm64:* Versions before 10.0.28000.2704 Vulnerable ·Microsoft
  • cpe:2.3:o:microsoft:windows_11_26h1:*:*:*:*:*:*:x64:* Versions before 10.0.28000.2704 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 10.0.14393.9418 Vulnerable ·Microsoft
  • cpe:2.3:o:microsoft:windows_server_2019:*:*:*:*:*:*:*:* Versions before 10.0.17763.9115 Vulnerable ·Microsoft
  • cpe:2.3:o:microsoft:windows_server_2022:*:*:*:*:*:*:*:* Versions before 10.0.20348.5440 Vulnerable ·Microsoft
  • cpe:2.3:o:microsoft:windows_server_2025:*:*:*:*:*:*:*:* Versions before 10.0.26100.33222 Vulnerable ·Microsoft

Remediation

Red Hat 5 advisories

  • RHSA-2026:60390 Released 2026-08-26 · Red Hat rating Important
    Red Hat Advanced Cluster Management for Kubernetes v2.13.11 security update
    • Red Hat Advanced Cluster Management for Kubernetes 2.13 registry.redhat.io/rhacm2/acm-governance-policy-addon-controller-rhel9, registry.redhat.io/rhacm2/acm-grafana-rhel9, registry.redhat.io/rhacm2/acm-multicluster-observability-addon-rhel9 +23
  • RHSA-2026:60388 Released 2026-08-26 · Red Hat rating Important
    Red Hat Advanced Cluster Management for Kubernetes v2.14.4 security update
    • Red Hat Advanced Cluster Management for Kubernetes 2.14 registry.redhat.io/rhacm2/acm-governance-policy-addon-controller-rhel9, registry.redhat.io/rhacm2/acm-grafana-rhel9, registry.redhat.io/rhacm2/acm-multicluster-observability-addon-rhel9 +26
  • RHSA-2026:60389 Released 2026-08-26 · Red Hat rating Important
    Red Hat Advanced Cluster Management for Kubernetes v2.15.6 security update
    • Red Hat Advanced Cluster Management for Kubernetes 2.15 registry.redhat.io/rhacm2/acm-governance-policy-addon-controller-rhel9, registry.redhat.io/rhacm2/acm-multicluster-observability-addon-rhel9, registry.redhat.io/rhacm2/acm-must-gather-rhel9 +19
Show 2 more Red Hat advisories
  • RHSA-2026:60386 Released 2026-08-26 · Red Hat rating Important
    Red Hat Advanced Cluster Management for Kubernetes v2.17.1 security update
    • Red Hat Advanced Cluster Management for Kubernetes 2.17 registry.redhat.io/rhacm2/acm-governance-policy-addon-controller-rhel9, registry.redhat.io/rhacm2/acm-grafana-rhel9, registry.redhat.io/rhacm2/acm-multicluster-observability-addon-rhel9 +31
  • RHSA-2026:57191 Released 2026-08-19 · Red Hat rating Important
    Red Hat Advanced Cluster Management for Kubernetes v2.16.3 security update
    • Red Hat Advanced Cluster Management for Kubernetes 2.16 registry.redhat.io/rhacm2/acm-grafana-rhel9, registry.redhat.io/rhacm2/acm-prometheus-config-reloader-rhel9, registry.redhat.io/rhacm2/acm-prometheus-rhel9 +15

Microsoft 14 updates

  • KB5123303
    Security Update
    • Windows Server 2022 10.0.20348.5499
    • Windows Server 2022 (Server Core installation) 10.0.20348.5499
  • KB5121003
    Security Update
    • Windows 11 Version 24H2 for ARM64-based Systems 10.0.26100.9168
    • Windows 11 Version 24H2 for x64-based Systems 10.0.26100.9168
    • Windows 11 Version 25H2 for ARM64-based Systems 10.0.26200.9168
    • Windows 11 Version 25H2 for x64-based Systems 10.0.26200.9168
  • KB5121000
    Security Update
    • Windows 11 Version 26H1 for ARM64-based Systems 10.0.28000.2704
    • Windows 11 version 26H1 for x64-based Systems 10.0.28000.2704
Show 11 more Microsoft updates
  • KB5120994
    Security Hotpatch Update
    • Windows 11 Version 24H2 for ARM64-based Systems 10.0.26100.9106, 10.0.26200.9106
    • Windows 11 Version 24H2 for x64-based Systems 10.0.26100.9106
    • Windows 11 Version 25H2 for ARM64-based Systems 10.0.26200.9106
    • Windows 11 Version 25H2 for x64-based Systems 10.0.26200.9106
  • KB5120418
    Security Update
    • Microsoft .NET Framework 3.5 AND 4.6.2/4.7/4.7.1/4.7.2 2.0.50727.8984 & 3.0.30729.8980 & 4.7.4144.0
    • Windows 10 Version 1607 for 32-bit Systems 10.0.14393.9418
    • Windows 10 Version 1607 for x64-based Systems 10.0.14393.9418
    • Windows Server 2016 10.0.14393.9418
    • Windows Server 2016 (Server Core installation) 10.0.14393.9418
  • KB5120386
    Monthly Rollup
    • Windows Server 2012 6.2.9200.26280
    • Windows Server 2012 (Server Core installation) 6.2.9200.26280
  • KB5120385
    Monthly Rollup
    • Windows Server 2012 R2 6.3.9600.23338
    • Windows Server 2012 R2 (Server Core installation) 6.3.9600.23338
  • KB5120249
    Security Update
    • Windows 10 Version 21H2 for 32-bit Systems 10.0.19044.7663
    • Windows 10 Version 21H2 for ARM64-based Systems 10.0.19044.7663
    • Windows 10 Version 21H2 for x64-based Systems 10.0.19044.7663
    • Windows 10 Version 22H2 for 32-bit Systems 10.0.19045.7663
    • Windows 10 Version 22H2 for ARM64-based Systems 10.0.19045.7663
    • Windows 10 Version 22H2 for x64-based Systems 10.0.19045.7663
  • KB5120242
    Security Update
    • Windows Server 2022 10.0.20348.5499
    • Windows Server 2022 (Server Core installation) 10.0.20348.5499
  • KB5120240
    Security Update
    • Windows 11 Version 23H2 for ARM64-based Systems 10.0.22631.7517
    • Windows 11 Version 23H2 for x64-based Systems 10.0.22631.7517
  • KB5120238
    Security Update
    • Windows 10 Version 1809 for 32-bit Systems 10.0.17763.9121
    • Windows 10 Version 1809 for x64-based Systems 10.0.17763.9121
    • Windows Server 2019 10.0.17763.9121
    • Windows Server 2019 (Server Core installation) 10.0.17763.9121
  • KB5120233
    Security Update
    • Windows Server 2025 10.0.26100.33296
    • Windows Server 2025 (Server Core installation) 10.0.26100.33296
  • KB5120229
    Security Hotpatch Update
    • Windows Server 2022 10.0.20348.5440
    • Windows Server 2022 (Server Core installation) 10.0.20348.5440
  • KB5120228
    Security Hotpatch Update
    • Windows Server 2025 10.0.26100.33222
    • Windows Server 2025 (Server Core installation) 10.0.26100.33222

Vendor assessments

Red Hat

Red Hat rating: Important. Red Hat's page for this CVE →

ProductStatusPlan or fix
Red Hat Advanced Cluster Management for Kubernetes 2.13Fixed RHSA-2026:60390
Red Hat Advanced Cluster Management for Kubernetes 2.14Fixed RHSA-2026:60388
Red Hat Advanced Cluster Management for Kubernetes 2.15Fixed RHSA-2026:60389
Red Hat Advanced Cluster Management for Kubernetes 2.16Fixed RHSA-2026:57191
Red Hat Advanced Cluster Management for Kubernetes 2.17Fixed RHSA-2026:60386
Not affected: 5 products
  • Red Hat Advanced Cluster Management for Kubernetes 2.13
  • Red Hat Advanced Cluster Management for Kubernetes 2.14
  • Red Hat Advanced Cluster Management for Kubernetes 2.15
  • Red Hat Advanced Cluster Management for Kubernetes 2.16
  • Red Hat Advanced Cluster Management for Kubernetes 2.17

Microsoft

Microsoft's page for this CVE →

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

Timeline

  1. 2026-10-02 Threatist record created from CVE-2026-66799
  2. 2026-10-03 Alias added: GHSA-cr27-wq5j-8m89

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