CVE-2021-34486 Microsoft Windows Event Tracing Privilege Escalation
An attacker can exploit a use-after-free flaw in Windows Event Tracing to elevate privileges on affected Windows systems.
- Exploited in the wild
- Since 28 Mar 2022
- Login needed
- Any signed-in user
- Attackable
- Local or same network only
- Victim action needed
- Not needed
- Fix
- None listed
What is CVE-2021-34486?
CVE-2021-34486 is a high-severity use after free vulnerability in Microsoft Windows 10 1809, published on 12 Aug 2021. It can only be exploited from the same machine or local network, with no action from the victim.
Official description
Windows Event Tracing Elevation of Privilege Vulnerability
Weakness: CWE-416
Which versions are affected by CVE-2021-34486?
It affects 8 products.
Products include Microsoft Windows 10 1809, Microsoft Windows 10 1909, Microsoft Windows 10 2004, Microsoft Windows 10 20h2, Microsoft Windows 10 21h1, Microsoft Windows Server 2004 and 2 more.
How do I fix CVE-2021-34486?
No fix has been published for CVE-2021-34486 yet. Limit exposure of the affected software until one is available. US federal agencies must fix it by 18 Apr 2022.
Upgrade to the fixed version. These bugs are found with fuzzing and sanitisers and avoided by memory-safe languages. More about Use after free.
Is CVE-2021-34486 being exploited?
Yes. Attackers have exploited CVE-2021-34486 in the wild since at least 28 Mar 2022.
Public exploit code: 2 proofs of concept on GitHub.
Other vulnerabilities in Microsoft Windows 10 1809
- CVE-2024-29988 Microsoft SmartScreen Prompt Security Feature Bypass
- CVE-2024-21412 Microsoft Windows Internet Shortcut Files Security Feature Bypass
- CVE-2025-62221 Microsoft Windows Use After Free
- CVE-2025-30400 Microsoft Windows DWM Core Library Use-After-Free
- CVE-2024-21338 Microsoft Windows Kernel Exposed IOCTL with Insufficient Access Control
Sources
Also known as GHSA-793m-wq3j-whvr.