Vulnerability · Published May 12, 2026 · Assigned by microsoft
CVE-2026-33838Windows Message Queuing (MSMQ) Elevation of Privilege Vulnerability
High 7.8
In plain English
A high-severity double free in Windows 10 Version 1607 from Microsoft. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 0.4% (higher than 34% of all known vulnerabilities).
Severity (CVSS 3.1)7.8High
Exploit odds (30 days)0.4%top 65.8% of all CVEs
Exploited in the wildNo reportsCISA SSVC: none
Attack toolingNoneno public tooling known
Official description
Double free in Windows Message Queuing allows an authorized attacker to elevate privileges locally.
Affected products (as reported)
| Vendor | Product | Versions |
|---|---|---|
| Microsoft | Windows 10 Version 1607 | 10.0.14393.0 – before 10.0.14393.9140 |
| Microsoft | Windows 10 Version 1809 | 10.0.17763.0 – before 10.0.17763.8755 |
| Microsoft | Windows 10 Version 21H2 | 10.0.19044.0 – before 10.0.19044.7291 |
| Microsoft | Windows 10 Version 22H2 | 10.0.19045.0 – before 10.0.19045.7417 |
| Microsoft | Windows 11 version 23H2 | 10.0.22631.0 – before 10.0.22631.7079 |
| Microsoft | Windows 11 Version 23H2 | 10.0.22631.0 – before 10.0.22631.7219 |
| Microsoft | Windows 11 Version 24H2 | 10.0.26100.0 – before 10.0.26100.8457 |
| Microsoft | Windows 11 Version 25H2 | 10.0.26200.0 – before 10.0.26200.8457 |
| Microsoft | Windows 11 version 26H1 | 10.0.28000.0 – before 10.0.28000.2113 |
| Microsoft | Windows Server 2012 | 6.2.9200.0 – before 6.2.9200.26079 |
| Microsoft | Windows Server 2012 (Server Core installation) | 6.2.9200.0 – before 6.2.9200.26079 |
| Microsoft | Windows Server 2012 R2 | 6.3.9600.0 – before 6.3.9600.23181 |
| Microsoft | Windows Server 2012 R2 (Server Core installation) | 6.3.9600.0 – before 6.3.9600.23181 |
| Microsoft | Windows Server 2016 | 10.0.14393.0 – before 10.0.14393.9140 |
| Microsoft | Windows Server 2016 (Server Core installation) | 10.0.14393.0 – before 10.0.14393.9140 |
| Microsoft | Windows Server 2019 | 10.0.17763.0 – before 10.0.17763.8755 |
| Microsoft | Windows Server 2019 (Server Core installation) | 10.0.17763.0 – before 10.0.17763.8755 |
| Microsoft | Windows Server 2022 | 10.0.20348.0 – before 10.0.20348.5139 |
| Microsoft | Windows Server 2022, 23H2 Edition (Server Core installation) | 10.0.25398.0 – before 10.0.25398.2330 |
| Microsoft | Windows Server 2025 | 10.0.26100.0 – before 10.0.26100.32860 |
| Microsoft | Windows Server 2025 (Server Core installation) | 10.0.26100.0 – before 10.0.26100.32860 |
Weakness: CWE-415 · Vector: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H/E:U/RL:O/RC:C
References
- Windows Message Queuing (MSMQ) Elevation of Privilege Vulnerability vendor-advisory, patch