CVE-2026-21530
Medium
Description
Double free in Windows Rich Text Edit allows an authorized attacker to elevate privileges locally.
SeverityMedium
CVSS6.7
Exploit probability—
Product
Microsoft Windows
PublishedMay 12, 2026
First seenMay 12, 2026
Weakness typeCWE-415CWE-415
How to fix
Update
- microsoft windows_10_160710.0.14393.9140 or later
- microsoft windows_10_180910.0.17763.8755 or later
- microsoft windows_10_21h210.0.19044.7291 or later
- microsoft windows_10_22h210.0.19045.7291 or later
- microsoft windows_11_23h210.0.22631.7079 or later
- microsoft windows_11_24h210.0.26100.8390 or later
- microsoft windows_11_25h210.0.26200.8457 or later
- microsoft windows_11_26h110.0.28000.2113 or later
- microsoft windows_server_201610.0.14393.9140 or later
- microsoft windows_server_201910.0.17763.8755 or later
- microsoft windows_server_202210.0.20348.5139 or later
- microsoft windows_server_2022_23h210.0.25398.2330 or later
Affected products
| Product | Affected versions | Fixed in |
|---|---|---|
| microsoft windows_10_1607 | v < 10.0.14393.9140 | 10.0.14393.9140 |
| microsoft windows_10_1809 | v < 10.0.17763.8755 | 10.0.17763.8755 |
| microsoft windows_10_21h2 | v < 10.0.19044.7291 | 10.0.19044.7291 |
| microsoft windows_10_22h2 | v < 10.0.19045.7291 | 10.0.19045.7291 |
| microsoft windows_11_23h2 | v < 10.0.22631.7079 | 10.0.22631.7079 |
| microsoft windows_11_24h2 | v < 10.0.26100.8390 | 10.0.26100.8390 |
| microsoft windows_11_25h2 | v < 10.0.26200.8457 | 10.0.26200.8457 |
| microsoft windows_11_26h1 | v < 10.0.28000.2113 | 10.0.28000.2113 |
| microsoft windows_server_2012 | No range specified, r2 | — |
| microsoft windows_server_2016 | v < 10.0.14393.9140 | 10.0.14393.9140 |
| microsoft windows_server_2019 | v < 10.0.17763.8755 | 10.0.17763.8755 |
| microsoft windows_server_2022 | v < 10.0.20348.5139 | 10.0.20348.5139 |
| microsoft windows_server_2022_23h2 | v < 10.0.25398.2330 | 10.0.25398.2330 |
| microsoft windows_server_2025 | v < 10.0.26100.32860 | 10.0.26100.32860 |
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