CVE-2026-27918
Race Condition in Windows Shell Enables Local Privilege Escalation
Publication date: 2026-04-14
Last updated on: 2026-04-22
Assigner: Microsoft Corporation
Description
Description
CVSS Scores
EPSS Scores
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Meta Information
Affected Vendors & Products
| Vendor | Product | Version / Range |
|---|---|---|
| microsoft | windows_10_1809 | to 10.0.17763.8644 (exc) |
| microsoft | windows_10_1809 | to 10.0.17763.8644 (exc) |
| microsoft | windows_10_21h2 | to 10.0.19044.7184 (exc) |
| microsoft | windows_10_21h2 | to 10.0.19044.7184 (exc) |
| microsoft | windows_10_21h2 | to 10.0.19044.7184 (exc) |
| microsoft | windows_10_22h2 | to 10.0.19045.7184 (exc) |
| microsoft | windows_10_22h2 | to 10.0.19045.7184 (exc) |
| microsoft | windows_10_22h2 | to 10.0.19045.7184 (exc) |
| microsoft | windows_11_23h2 | to 10.0.22631.6936 (exc) |
| microsoft | windows_11_23h2 | to 10.0.22631.6936 (exc) |
| microsoft | windows_11_24h2 | to 10.0.26100.8246 (exc) |
| microsoft | windows_11_24h2 | to 10.0.26100.8246 (exc) |
| microsoft | windows_11_25h2 | to 10.0.26200.8246 (exc) |
| microsoft | windows_11_25h2 | to 10.0.26200.8246 (exc) |
| microsoft | windows_11_26h1 | to 10.0.28000.1836 (exc) |
| microsoft | windows_11_26h1 | to 10.0.28000.1836 (exc) |
| microsoft | windows_server_2019 | to 10.0.17763.8644 (exc) |
| microsoft | windows_server_2022 | to 10.0.20348.5020 (exc) |
| microsoft | windows_server_2022_23h2 | to 10.0.25398.2274 (exc) |
| microsoft | windows_server_2025 | to 10.0.26100.32690 (exc) |
Helpful Resources
Exploitability
| CWE ID | Description |
|---|---|
| CWE-362 | The product contains a concurrent code sequence that requires temporary, exclusive access to a shared resource, but a timing window exists in which the shared resource can be modified by another code sequence operating concurrently. |
Attack-Flow Graph
AI Powered Q&A
How does this vulnerability affect compliance with common standards and regulations (like GDPR, HIPAA)?:
This vulnerability allows an authorized attacker to elevate privileges locally through a race condition in Windows Shell.
Elevation of privilege vulnerabilities can potentially impact compliance with standards such as GDPR and HIPAA by increasing the risk of unauthorized access to sensitive data or systems.
However, no specific information is provided regarding direct effects on compliance with these regulations.
What immediate steps should I take to mitigate this vulnerability?
To mitigate this vulnerability, apply the security updates provided by Microsoft for Windows Shell as soon as possible to fix the race condition that allows privilege escalation.
Can you explain this vulnerability to me?
This vulnerability is a race condition in the Windows Shell where concurrent execution using a shared resource occurs without proper synchronization. This flaw allows an authorized attacker to elevate their privileges locally on the affected system.
How can this vulnerability impact me? :
An attacker who already has some level of access to the system can exploit this vulnerability to gain higher privileges. This means they could perform actions that normally require elevated permissions, potentially leading to full system compromise, unauthorized data access, or disruption of system integrity.