CVE-2026-41091 Microsoft Defender Link Following
An authorized local attacker can elevate privileges by exploiting improper link resolution in Microsoft Defender.
- Exploited in the wild
- Since 20 May 2026
- Login needed
- Any signed-in user
- Attackable
- Local or same network only
- Victim action needed
- Not needed
- Fix
- None listed
What is CVE-2026-41091?
CVE-2026-41091 is a high-severity path traversal vulnerability in Microsoft Malware Protection Engine, published on 20 May 2026. It can only be exploited from the same machine or local network, with no action from the victim.
Official description
Improper link resolution before file access ('link following') in Microsoft Defender allows an authorized attacker to elevate privileges locally.
Weakness: CWE-59
Which versions are affected by CVE-2026-41091?
It affects 1 product.
Products include Microsoft Malware Protection Engine.
How do I fix CVE-2026-41091?
No fix has been published for CVE-2026-41091 yet. Limit exposure of the affected software until one is available. US federal agencies must fix it by 3 Jun 2026.
Upgrade, and resolve every user-supplied path against an allowed base folder before opening it. More about Path traversal.
Is CVE-2026-41091 being exploited?
Yes. Attackers have exploited CVE-2026-41091 in the wild since at least 20 May 2026.
Public exploit code: 4 proofs of concept on GitHub.
Other vulnerabilities in Microsoft Malware Protection Engine
- CVE-2013-1346 Memory corruption in n/a
- CVE-2026-45584 Microsoft Defender Remote Code Execution Vulnerability
- CVE-2026-69414 Microsoft Defender Elevation of Privilege Vulnerability
- CVE-2026-55011 Microsoft Defender Remote Code Execution Vulnerability
- CVE-2026-55012 Microsoft Defender Remote Code Execution Vulnerability
Sources
Also known as GHSA-h776-j9jw-992p.