CVE-2026-34330
Modified
Modified - Updated After Analysis
BaseFortify
Vulnerability report for CVE-2026-34330, including description, CVSS score, EPSS score, affected products, exploitability, helpful resources, and attack-flow context.
Publication date: 2026-05-12
Last updated on: 2026-06-01
Assigner: Microsoft Corporation
Description
Description
Concurrent execution using shared resource with improper synchronization ('race condition') in Windows Win32K - GRFX allows an authorized attacker to elevate privileges locally.
CVSS Scores
EPSS Scores
| Probability: | |
| Percentile: |
Meta Information
Affected Vendors & Products
| Vendor | Product | Version / Range |
|---|---|---|
| microsoft | windows_10_1607 | to 10.0.14393.9140 (exc) |
| microsoft | windows_10_1809 | to 10.0.17763.8755 (exc) |
| microsoft | windows_10_21h2 | to 10.0.19044.7291 (exc) |
| microsoft | windows_10_22h2 | to 10.0.19045.7291 (exc) |
| microsoft | windows_11_23h2 | to 10.0.22631.7079 (exc) |
| microsoft | windows_11_24h2 | to 10.0.26100.8390 (exc) |
| microsoft | windows_11_25h2 | to 10.0.26200.8390 (exc) |
| microsoft | windows_11_26h1 | to 10.0.28000.2113 (exc) |
| microsoft | windows_server_2012 | * |
| microsoft | windows_server_2012 | r2 |
| microsoft | windows_server_2016 | to 10.0.14393.9140 (exc) |
| microsoft | windows_server_2019 | to 10.0.17763.8755 (exc) |
| microsoft | windows_server_2022 | to 10.0.20348.5074 (exc) |
| microsoft | windows_server_2022_23h2 | to 10.0.25398.2330 (exc) |
| microsoft | windows_server_2025 | to 10.0.26100.32772 (exc) |
Helpful Resources
Exploitability
| CWE ID | Description |
|---|---|
| CWE-416 | The product reuses or references memory after it has been freed. At some point afterward, the memory may be allocated again and saved in another pointer, while the original pointer references a location somewhere within the new allocation. Any operations using the original pointer are no longer valid because the memory "belongs" to the code that operates on the new pointer. |
| CWE-190 | The product performs a calculation that can produce an integer overflow or wraparound when the logic assumes that the resulting value will always be larger than the original value. This occurs when an integer value is incremented to a value that is too large to store in the associated representation. When this occurs, the value may become a very small or negative number. |