CVE-2021-26863 in the critical feed json
Windows Win32k Elevation of Privilege Vulnerability
published 2021-03-11 5 y ago modified 2026-08-19 2 mo ago also EUVD-2021-13647
- cvss
- 7.8
- version 3.1, CNA
- cisa kev
- Not listed
- not in CISA's catalog
- epss
- 11.9%
- EPSS 11.9% chance of exploitation in 30 days, percentile 96%
- public exploits
- 0
- none known
Summary
Windows Win32k Elevation of Privilege Vulnerability
Patch / fix
- Microsoft Windows 10 Version 1803 10.0.17134.2087
- Microsoft Windows 10 Version 1809 10.0.17763.1817
- Microsoft Windows 10 Version 1909 10.0.18363.1440
- Microsoft Windows 10 Version 2004 10.0.19043.867
- Microsoft Windows 10 Version 20H2 10.0.19043.867
- Microsoft Windows Server 2019 10.0.17763.1817
- Microsoft Windows Server 2019 (Server Core installation) 10.0.17763.1817
- Microsoft Windows Server version 2004 10.0.19043.867
- Microsoft Windows Server version 20H2 10.0.19043.867
- Microsoft Windows Server, version 1909 (Server Core installation) 10.0.18363.1440
Exploit prediction
11.94% chance of exploitation in the next 30 days, higher than 96% of all scored CVEs (FIRST EPSS, 2026-11-08).
Exploits and checks
- packetstormsecurity.com http://packetstormsecurity.com/files/161768/Microsoft-Windows-Kernel-NtGdiGetDeviceCapsAll-Race-Condition-Use-After-Free.html referenced PoC, tagged "exploit" by a source, unverified
CVSS scores
| assigned by | version | score | vector |
|---|---|---|---|
| CNA | 3.1 | 7.0 | CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H/E:U/RL:O/RC:C |
| CNA | 3.1 | 7.0 | CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H |
| CNA | 3.1 | 7.8 | CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H |
| NVD | 2.0 | 7.2 | AV:L/AC:L/Au:N/C:C/I:C/A:C |
Affected products
- Microsoft Windows 10 Version 1803
- Microsoft Windows 10 Version 1809
- Microsoft Windows 10 Version 1909
- Microsoft Windows 10 Version 2004
- Microsoft Windows 10 Version 20H2
- Microsoft Windows Server 2019
- Microsoft Windows Server 2019 (Server Core installation)
- Microsoft Windows Server version 2004
- Microsoft Windows Server version 20H2
- Microsoft Windows Server, version 1909 (Server Core installation)
Classification
- Weakness
-
- CWE-269 Improper Privilege Management
References
-
msrc.microsoft.com
/update-guide/vulnerability/CVE-2021-26863
vendor-advisory, patch
-
portal.msrc.microsoft.com
/en-US/security-guidance/advisory/CVE-2021-26863
patch, vendor-advisory
-
packetstormsecurity.com
/files/161768/Microsoft-Windows-Kernel-NtGdiGetDeviceCapsAll-Race-Condition-Use-After-Free.html
exploit, third-party-advisory
Sources
- CVE List CVE-2021-26863
- NVD CVE-2021-26863
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