Windows Key Guard Security Feature Bypass Vulnerability
Priority LOW 24CWE-1240Published · Updated
Key facts
- Attack vector
- Local
- Privileges required
- Low
- 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 · CNA. Fix status from CNA and Microsoft. Impact type from Microsoft.
Summary
Use of a cryptographic primitive with a risky implementation in Windows Key Guard allows an authorized attacker to bypass a security feature locally.
Why it matters now
Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.0027 19th percentileScored 2026-11-07
Fix Fixed Microsoft: 6 updates
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
| Vendor | Product | Affected versions | Fixed in | Status | Source |
|---|---|---|---|---|---|
| Microsoft | Windows 10 Version 1809 | 10.0.17763.0 to before 10.0.17763.9020 | 10.0.17763.9020 | Patch available | CNA |
| Microsoft | Windows 10 Version 21H2 | 10.0.19044.0 to before 10.0.19044.7548 | 10.0.19044.7548 | Patch available | CNA |
| Microsoft | Windows 10 Version 22H2 | 10.0.19045.0 to before 10.0.19045.7548 | 10.0.19045.7548 | Patch available | CNA |
| Microsoft | Windows 11 Version 24H2 | 10.0.26100.0 to before 10.0.26100.8875 | 10.0.26100.8875 | Patch available | CNA |
| Microsoft | Windows 11 Version 25H2 | 10.0.26200.0 to before 10.0.26200.8875 | 10.0.26200.8875 | Patch available | CNA |
| Microsoft | Windows 11 version 26H1 | 10.0.28000.0 to before 10.0.28000.2525 | 10.0.28000.2525 | Patch available | CNA |
| Microsoft | Windows Server 2019 | 10.0.17763.0 to before 10.0.17763.9020 | 10.0.17763.9020 | Patch available | CNA |
| Microsoft | Windows Server 2019 (Server Core installation) | 10.0.17763.0 to before 10.0.17763.9020 | 10.0.17763.9020 | Patch available | CNA |
| Microsoft | Windows Server 2022 | 10.0.20348.0 to before 10.0.20348.5386 | 10.0.20348.5386 | Patch available | CNA |
| Microsoft | Windows Server 2025 | 10.0.26100.0 to before 10.0.26100.33158 | 10.0.26100.33158 | Patch available | CNA |
| Microsoft | Windows Server 2025 (Server Core installation) | 10.0.26100.0 to before 10.0.26100.33158 | 10.0.26100.33158 | Patch available | CNA |
- Windows 10 Version 1809 VendorMicrosoft Affected 10.0.17763.0 to before 10.0.17763.9020 Fixed in 10.0.17763.9020 Patch available CNA
- Windows 10 Version 21H2 VendorMicrosoft Affected 10.0.19044.0 to before 10.0.19044.7548 Fixed in 10.0.19044.7548 Patch available CNA
- Windows 10 Version 22H2 VendorMicrosoft Affected 10.0.19045.0 to before 10.0.19045.7548 Fixed in 10.0.19045.7548 Patch available CNA
- Windows 11 Version 24H2 VendorMicrosoft Affected 10.0.26100.0 to before 10.0.26100.8875 Fixed in 10.0.26100.8875 Patch available CNA
- Windows 11 Version 25H2 VendorMicrosoft Affected 10.0.26200.0 to before 10.0.26200.8875 Fixed in 10.0.26200.8875 Patch available CNA
- Windows 11 version 26H1 VendorMicrosoft Affected 10.0.28000.0 to before 10.0.28000.2525 Fixed in 10.0.28000.2525 Patch available CNA
- Windows Server 2019 VendorMicrosoft Affected 10.0.17763.0 to before 10.0.17763.9020 Fixed in 10.0.17763.9020 Patch available CNA
- Windows Server 2019 (Server Core installation) VendorMicrosoft Affected 10.0.17763.0 to before 10.0.17763.9020 Fixed in 10.0.17763.9020 Patch available CNA
- Windows Server 2022 VendorMicrosoft Affected 10.0.20348.0 to before 10.0.20348.5386 Fixed in 10.0.20348.5386 Patch available CNA
- Windows Server 2025 VendorMicrosoft Affected 10.0.26100.0 to before 10.0.26100.33158 Fixed in 10.0.26100.33158 Patch available CNA
- Windows Server 2025 (Server Core installation) VendorMicrosoft Affected 10.0.26100.0 to before 10.0.26100.33158 Fixed in 10.0.26100.33158 Patch available CNA
CPE configurations NVD · 17
| CPE | Versions | Role | Vendor |
|---|---|---|---|
| cpe:2.3:o:microsoft:windows_10_1809:*:*:*:*:*:*:x64:* | before 10.0.17763.9020 | Vulnerable | Microsoft |
| cpe:2.3:o:microsoft:windows_10_1809:*:*:*:*:*:*:x86:* | before 10.0.17763.9020 | Vulnerable | Microsoft |
| cpe:2.3:o:microsoft:windows_10_21h2:*:*:*:*:*:*:arm64:* | before 10.0.19044.7548 | Vulnerable | Microsoft |
| cpe:2.3:o:microsoft:windows_10_21h2:*:*:*:*:*:*:x64:* | before 10.0.19044.7548 | Vulnerable | Microsoft |
| cpe:2.3:o:microsoft:windows_10_21h2:*:*:*:*:*:*:x86:* | before 10.0.19044.7548 | Vulnerable | Microsoft |
| cpe:2.3:o:microsoft:windows_10_22h2:*:*:*:*:*:*:arm64:* | before 10.0.19045.7548 | Vulnerable | Microsoft |
| cpe:2.3:o:microsoft:windows_10_22h2:*:*:*:*:*:*:x64:* | before 10.0.19045.7548 | Vulnerable | Microsoft |
| cpe:2.3:o:microsoft:windows_10_22h2:*:*:*:*:*:*:x86:* | before 10.0.19045.7548 | Vulnerable | Microsoft |
| cpe:2.3:o:microsoft:windows_11_24h2:*:*:*:*:*:*:arm64:* | before 10.0.26100.8875 | Vulnerable | Microsoft |
| cpe:2.3:o:microsoft:windows_11_24h2:*:*:*:*:*:*:x64:* | before 10.0.26100.8875 | Vulnerable | Microsoft |
- cpe:2.3:o:microsoft:windows_10_1809:*:*:*:*:*:*:x64:* Versions before 10.0.17763.9020 Vulnerable ·Microsoft
- cpe:2.3:o:microsoft:windows_10_1809:*:*:*:*:*:*:x86:* Versions before 10.0.17763.9020 Vulnerable ·Microsoft
- cpe:2.3:o:microsoft:windows_10_21h2:*:*:*:*:*:*:arm64:* Versions before 10.0.19044.7548 Vulnerable ·Microsoft
- cpe:2.3:o:microsoft:windows_10_21h2:*:*:*:*:*:*:x64:* Versions before 10.0.19044.7548 Vulnerable ·Microsoft
- cpe:2.3:o:microsoft:windows_10_21h2:*:*:*:*:*:*:x86:* Versions before 10.0.19044.7548 Vulnerable ·Microsoft
- cpe:2.3:o:microsoft:windows_10_22h2:*:*:*:*:*:*:arm64:* Versions before 10.0.19045.7548 Vulnerable ·Microsoft
- cpe:2.3:o:microsoft:windows_10_22h2:*:*:*:*:*:*:x64:* Versions before 10.0.19045.7548 Vulnerable ·Microsoft
- cpe:2.3:o:microsoft:windows_10_22h2:*:*:*:*:*:*:x86:* Versions before 10.0.19045.7548 Vulnerable ·Microsoft
- cpe:2.3:o:microsoft:windows_11_24h2:*:*:*:*:*:*:arm64:* Versions before 10.0.26100.8875 Vulnerable ·Microsoft
- cpe:2.3:o:microsoft:windows_11_24h2:*:*:*:*:*:*:x64:* Versions before 10.0.26100.8875 Vulnerable ·Microsoft
Show 7 more CPE
| CPE | Versions | Role | Vendor |
|---|---|---|---|
| cpe:2.3:o:microsoft:windows_11_25h2:*:*:*:*:*:*:arm64:* | before 10.0.26200.8875 | Vulnerable | Microsoft |
| cpe:2.3:o:microsoft:windows_11_25h2:*:*:*:*:*:*:x64:* | before 10.0.26200.8875 | Vulnerable | Microsoft |
| cpe:2.3:o:microsoft:windows_11_26h1:*:*:*:*:*:*:x64:* | before 10.0.28000.2269 | Vulnerable | Microsoft |
| cpe:2.3:o:microsoft:windows_11_26h1:*:*:*:*:*:*:arm64:* | before 10.0.28000.2525 | Vulnerable | Microsoft |
| cpe:2.3:o:microsoft:windows_server_2019:*:*:*:*:*:*:*:* | before 10.0.17763.9020 | Vulnerable | Microsoft |
| cpe:2.3:o:microsoft:windows_server_2022:*:*:*:*:*:*:*:* | before 10.0.20348.5386 | Vulnerable | Microsoft |
| cpe:2.3:o:microsoft:windows_server_2025:*:*:*:*:*:*:*:* | before 10.0.26100.33158 | Vulnerable | Microsoft |
- cpe:2.3:o:microsoft:windows_11_25h2:*:*:*:*:*:*:arm64:* Versions before 10.0.26200.8875 Vulnerable ·Microsoft
- cpe:2.3:o:microsoft:windows_11_25h2:*:*:*:*:*:*:x64:* Versions before 10.0.26200.8875 Vulnerable ·Microsoft
- cpe:2.3:o:microsoft:windows_11_26h1:*:*:*:*:*:*:x64:* Versions before 10.0.28000.2269 Vulnerable ·Microsoft
- cpe:2.3:o:microsoft:windows_11_26h1:*:*:*:*:*:*:arm64:* Versions before 10.0.28000.2525 Vulnerable ·Microsoft
- cpe:2.3:o:microsoft:windows_server_2019:*:*:*:*:*:*:*:* Versions before 10.0.17763.9020 Vulnerable ·Microsoft
- cpe:2.3:o:microsoft:windows_server_2022:*:*:*:*:*:*:*:* Versions before 10.0.20348.5386 Vulnerable ·Microsoft
- cpe:2.3:o:microsoft:windows_server_2025:*:*:*:*:*:*:*:* Versions before 10.0.26100.33158 Vulnerable ·Microsoft
Remediation
Microsoft 6 updates
- Security Update
- Windows 11 Version 24H2 for ARM64-based Systems 10.0.26100.8875
- Windows 11 Version 24H2 for x64-based Systems 10.0.26100.8875
- Windows 11 Version 25H2 for ARM64-based Systems 10.0.26200.8875
- Windows 11 Version 25H2 for x64-based Systems 10.0.26200.8875
- Security Update
- Windows 11 Version 26H1 for ARM64-based Systems 10.0.28000.2525
- Windows 11 version 26H1 for x64-based Systems 10.0.28000.2525
- Security Update
- Windows Server 2022 10.0.20348.5386
- Windows Server 2022 (Server Core installation) 10.0.20348.5386
Show 3 more Microsoft updates
- Security Update
- Windows 10 Version 21H2 for 32-bit Systems 10.0.19044.7548
- Windows 10 Version 21H2 for ARM64-based Systems 10.0.19044.7548
- Windows 10 Version 21H2 for x64-based Systems 10.0.19044.7548
- Windows 10 Version 22H2 for 32-bit Systems 10.0.19045.7548
- Windows 10 Version 22H2 for ARM64-based Systems 10.0.19045.7548, 10.0.19044.7548
- Windows 10 Version 22H2 for x64-based Systems 10.0.19045.7548
- Security Update
- Windows 10 Version 1809 for 32-bit Systems 10.0.17763.9020
- Windows 10 Version 1809 for x64-based Systems 10.0.17763.9020
- Windows Server 2019 10.0.17763.9020
- Windows Server 2019 (Server Core installation) 10.0.17763.9020
- Security Update
- Windows Server 2025 10.0.26100.33158
- Windows Server 2025 (Server Core installation) 10.0.26100.33158
Vendor assessments
Microsoft
Microsoft's page for this CVE →
- Impact
- Security Feature Bypass
- Exploited
- No
- Publicly disclosed
- No
- Exploitability
- Exploitation Less Likely
Timeline
- 2026-10-02 Threatist record created from CVE-2026-50303
- 2026-10-03 Alias added: GHSA-4gjp-9g3v-jfmp
References
More Microsoft Windows 10 1809 vulnerabilities
- 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
Sources
- CVE-2026-50303 · CVE Program
- CVE-2026-50303 · NVD
- FIRST EPSS
- GHSA-4gjp-9g3v-jfmp · GitHub Advisory Database · CC BY 4.0
- CVE-2026-50303 · Microsoft Security Update Guide
This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences