7.0
High
CVE-2026-21253 Use after free in Mailslot File System allows an authorized attacker to elevate privileges locally
Description
Use after free in Mailslot File System allows an authorized attacker to elevate privileges locally.
Affected products and versions
| Product | Affected versions | Fixed in |
|---|---|---|
| Windows 11 version 26H1 10.0 | 10.0.28000.0 → < 10.0.28000.1575 | 10.0.28000.1575 |
| Windows Server 2022 10.0 | 10.0.20348.0 → < 10.0.20348.4773 | 10.0.20348.4773 |
| Windows 10 Version 21H2 10.0 | 10.0.19044.0 → < 10.0.19044.6937 | 10.0.19044.6937 |
| Windows 10 Version 1809 10.0 | 10.0.17763.0 → < 10.0.17763.8389 | 10.0.17763.8389 |
| Windows 10 Version 22H2 10.0 | 10.0.19045.0 → < 10.0.19045.6937 | 10.0.19045.6937 |
| Windows Server 2025 (Server Core installation) 10.0 | 10.0.26100.0 → < 10.0.26100.32370 | 10.0.26100.32370 |
| Windows 11 Version 25H2 10.0 | 10.0.26200.0 → < 10.0.26200.7840 | 10.0.26200.7840 |
| Windows 11 version 22H3 10.0 | 10.0.22631.0 → < 10.0.22631.6649 | 10.0.22631.6649 |
| Windows 11 Version 23H2 10.0 | 10.0.22631.0 → < 10.0.22631.6649 | 10.0.22631.6649 |
Show the 12 other branches Hide the 12 other branches
| Product | Affected versions | Fixed in |
|---|---|---|
| Windows Server 2022, 23H2 Edition (Server Core installation) 10.0 | 10.0.25398.0 → < 10.0.25398.2149 | 10.0.25398.2149 |
| Windows 11 Version 24H2 10.0 | 10.0.26100.0 → < 10.0.26100.7840 | 10.0.26100.7840 |
| Windows Server 2025 10.0 | 10.0.26100.0 → < 10.0.26100.32370 | 10.0.26100.32370 |
| Windows Server 2016 10.0 | 10.0.14393.0 → < 10.0.14393.8868 | 10.0.14393.8868 |
| Windows 10 Version 1607 10.0 | 10.0.14393.0 → < 10.0.14393.8868 | 10.0.14393.8868 |
| Windows Server 2016 (Server Core installation) 10.0 | 10.0.14393.0 → < 10.0.14393.8868 | 10.0.14393.8868 |
| Windows Server 2012 (Server Core installation) 6.2 | 6.2.9200.0 → < 6.2.9200.25923 | 6.2.9200.25923 |
| Windows Server 2012 R2 6.3 | 6.3.9600.0 → < 6.3.9600.23022 | 6.3.9600.23022 |
| Windows Server 2012 6.2 | 6.2.9200.0 → < 6.2.9200.25923 | 6.2.9200.25923 |
| Windows Server 2012 R2 (Server Core installation) 6.3 | 6.3.9600.0 → < 6.3.9600.23022 | 6.3.9600.23022 |
| Windows Server 2019 10.0 | 10.0.17763.0 → < 10.0.17763.8389 | 10.0.17763.8389 |
| Windows Server 2019 (Server Core installation) 10.0 | 10.0.17763.0 → < 10.0.17763.8389 | 10.0.17763.8389 |
References
- Mailslot File System Elevation of Privilege Vulnerability msrc.microsoft.com
Timeline
- Published
- Last modified
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