---
id: CVE-2026-50303
title: Windows Key Guard Security Feature Bypass Vulnerability
summary: >-
  Use of a cryptographic primitive with a risky implementation in Windows Key
  Guard allows an authorized attacker to bypass a security feature locally.
severity: medium
cvss: 5.5
cvssVector: 'CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N/E:U/RL:O/RC:C'
cvssSource: cna
cwe:
  - CWE-1240
vendor: Microsoft
product: Windows 10 Version 1809
affected:
  - windows_10_version_1809 >= 10.0.17763.0 < 10.0.17763.9020
  - windows_10_version_21h2 >= 10.0.19044.0 < 10.0.19044.7548
  - windows_10_version_22h2 >= 10.0.19045.0 < 10.0.19045.7548
  - windows_11_version_24h2 >= 10.0.26100.0 < 10.0.26100.8875
  - windows_11_version_25h2 >= 10.0.26200.0 < 10.0.26200.8875
  - windows_11_version_26h1 >= 10.0.28000.0 < 10.0.28000.2525
  - windows_server_2019 >= 10.0.17763.0 < 10.0.17763.9020
  - >-
    windows_server_2019_server_core_installation >= 10.0.17763.0 <
    10.0.17763.9020
  - windows_server_2022 >= 10.0.20348.0 < 10.0.20348.5386
  - windows_server_2025 >= 10.0.26100.0 < 10.0.26100.33158
  - >-
    windows_server_2025_server_core_installation >= 10.0.26100.0 <
    10.0.26100.33158
ssvc:
  exploitation: none
  automatable: 'no'
  technicalImpact: partial
  timestamp: '2026-07-14T19:22:55.018431Z'
published: '2026-07-14'
updated: '2026-09-17'
sourceUpdated: '2026-09-17T22:30:17.552Z'
source: CVEORG
sourceUrl: 'https://www.cve.org/CVERecord?id=CVE-2026-50303'
references:
  - url: 'https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-50303'
    label: Windows Key Guard Security Feature Bypass Vulnerability
tags:
  - cve.org
epss: 0.0027
epssPercentile: 0.17012
ingestedAt: '2026-09-08T17:06:31.922Z'
---

## Overview

Use of a cryptographic primitive with a risky implementation in Windows Key Guard allows an authorized attacker to bypass a security feature locally.

## Affected

- `windows_10_version_1809 >= 10.0.17763.0 < 10.0.17763.9020`
- `windows_10_version_21h2 >= 10.0.19044.0 < 10.0.19044.7548`
- `windows_10_version_22h2 >= 10.0.19045.0 < 10.0.19045.7548`
- `windows_11_version_24h2 >= 10.0.26100.0 < 10.0.26100.8875`
- `windows_11_version_25h2 >= 10.0.26200.0 < 10.0.26200.8875`
- `windows_11_version_26h1 >= 10.0.28000.0 < 10.0.28000.2525`
- `windows_server_2019 >= 10.0.17763.0 < 10.0.17763.9020`
- `windows_server_2019_server_core_installation >= 10.0.17763.0 < 10.0.17763.9020`
- `windows_server_2022 >= 10.0.20348.0 < 10.0.20348.5386`
- `windows_server_2025 >= 10.0.26100.0 < 10.0.26100.33158`
- `windows_server_2025_server_core_installation >= 10.0.26100.0 < 10.0.26100.33158`

## Remediation

Refer to the linked advisories for vendor-supplied fixes and affected version ranges.