CVE-2026-108135 Windows Backup Engine Elevation of Privilege Vulnerability
An authorized local attacker can elevate privileges by exploiting improper link resolution in the Windows Backup Engine.
- 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-2026-108135?
CVE-2026-108135 is a high-severity path traversal vulnerability in Microsoft Windows 10 21h2, 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
Improper link resolution before file access ('link following') in Windows Backup Engine allows an authorized attacker to elevate privileges locally.
Weakness: CWE-59
Which versions are affected by CVE-2026-108135?
It affects 7 products.
Products include Microsoft Windows 10 21h2, Microsoft Windows 10 22h2, Microsoft Windows 11 23h2, Microsoft Windows 11 24h2, Microsoft Windows 11 25h2, Microsoft Windows 11 26h1 and 1 more.
How do I fix CVE-2026-108135?
No fix has been published for CVE-2026-108135 yet. Limit exposure of the affected software until one is available.
Upgrade, and resolve every user-supplied path against an allowed base folder before opening it. More about Path traversal.
Is CVE-2026-108135 being exploited?
There is no known exploitation of CVE-2026-108135 in the wild and no public exploit code.
Other vulnerabilities in Microsoft Windows 10 21h2
- CVE-2025-21333 Microsoft Windows Hyper-V NT Kernel Integration VSP Heap-based Buffer Overflow
- CVE-2025-21334 Microsoft Windows Hyper-V NT Kernel Integration VSP Use-After-Free
- CVE-2025-21335 Microsoft Windows Hyper-V NT Kernel Integration VSP Use-After-Free
- CVE-2026-42904 Windows TCP/IP Elevation of Privilege Vulnerability
- CVE-2026-105733 Windows Hyper-V Remote Code Execution Vulnerability
Sources
Also known as GHSA-wfr6-h9hr-j5vv.