CVE-2026-83666 Active Directory Certificate Services (AD CS) Elevation of Privilege Vulnerability
A race condition in Active Directory Certificate Services allows an authorized local attacker to elevate privileges.
- Exploited in the wild
- Not known
- Login needed
- Any signed-in user
- Attackable
- Local or same network only
- Victim action needed
- Not needed
- Fix
- None listed
What is CVE-2026-83666?
CVE-2026-83666 is a high-severity vulnerability in Microsoft Windows 10 1607, published on 13 Oct 2026. It can only be exploited from the same machine or local network, with no action from the victim.
Official description
Concurrent execution using shared resource with improper synchronization ('race condition') in Active Directory Certificate Services (AD CS) allows an authorized attacker to elevate privileges locally.
Weakness: CWE-362
Which versions are affected by CVE-2026-83666?
It affects 7 products.
Products include Microsoft Windows 10 1607, Microsoft Windows 10 1809, Microsoft Windows Server 2012, Microsoft Windows Server 2016, Microsoft Windows Server 2019, Microsoft Windows Server 2022 and 1 more.
How do I fix CVE-2026-83666?
No fix has been published for CVE-2026-83666 yet. Limit exposure of the affected software until one is available.
Is CVE-2026-83666 being exploited?
There is no known exploitation of CVE-2026-83666 in the wild and no public exploit code.
Other vulnerabilities in Microsoft Windows 10 1607
- CVE-2026-33824 Microsoft Internet Key Exchange (IKE) Service Extensions Double Free
- CVE-2026-21510 Microsoft Windows Shell Protection Mechanism Failure
- CVE-2026-21513 Microsoft MSHTML Framework Protection Mechanism Failure
- CVE-2023-32049 Microsoft Windows Defender SmartScreen Security Feature Bypass
- CVE-2023-29360 Microsoft Streaming Service Untrusted Pointer Dereference
Sources
Also known as GHSA-8xp8-49xf-pww4.