Vulnerability · Published Apr 14, 2026 · Assigned by microsoft
CVE-2026-33826Windows Active Directory Remote Code Execution Vulnerability
High 8.0
In plain English
A high-severity improper input validation in Windows Server 2012 R2 from Microsoft. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 0.5% (higher than 45% of all known vulnerabilities). Ready-made attack tooling exists: public proof-of-concept code.
Severity (CVSS 3.1)8.0High
Exploit odds (30 days)0.5%top 54.7% of all CVEs
Exploited in the wildNo reportsCISA SSVC: none
Attack tooling1Public PoC
Official description
Improper input validation in Windows Active Directory allows an authorized attacker to execute code over an adjacent network.
Affected products (as reported)
| Vendor | Product | Versions |
|---|---|---|
| Microsoft | Windows Server 2012 R2 | 6.3.9600.0 – before 6.3.9600.23132 |
| Microsoft | Windows Server 2012 R2 (Server Core installation) | 6.3.9600.0 – before 6.3.9600.23132 |
| Microsoft | Windows Server 2016 | 10.0.14393.0 – before 10.0.14393.9060 |
| Microsoft | Windows Server 2016 (Server Core installation) | 10.0.14393.0 – before 10.0.14393.9060 |
| Microsoft | Windows Server 2019 | 10.0.17763.0 – before 10.0.17763.8644 |
| Microsoft | Windows Server 2019 (Server Core installation) | 10.0.17763.0 – before 10.0.17763.8644 |
| Microsoft | Windows Server 2022 | 10.0.20348.0 – before 10.0.20348.5020 |
| Microsoft | Windows Server 2022, 23H2 Edition (Server Core installation) | 10.0.25398.0 – before 10.0.25398.2274 |
| Microsoft | Windows Server 2025 | 10.0.26100.0 – before 10.0.26100.32690 |
| Microsoft | Windows Server 2025 (Server Core installation) | 10.0.26100.0 – before 10.0.26100.32690 |
Weakness: CWE-20 · Vector: CVSS:3.1/AV:A/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H/E:U/RL:O/RC:C
References
- Windows Active Directory Remote Code Execution Vulnerability vendor-advisory, patch