CVE-2026-58638 Windows Boot Loader Security Feature Bypass Vulnerability
An authorized local attacker can bypass a security feature in the Windows Boot Loader due to a missing cryptographic step.
- Exploited in the wild
- Not known
- Login needed
- An administrator
- Attackable
- Local or same network only
- Victim action needed
- Not needed
- Fix
- None listed
What is CVE-2026-58638?
CVE-2026-58638 is a medium-severity vulnerability in Microsoft Windows 10 1809, published on 14 Jul 2026. It can only be exploited from the same machine or local network, with no action from the victim.
Official description
Missing cryptographic step in Windows Boot Loader allows an authorized attacker to bypass a security feature locally.
Weakness: CWE-325
Which versions are affected by CVE-2026-58638?
It affects 12 products.
Products include Microsoft Windows 10 1809, Microsoft Windows 10 21h2, Microsoft Windows 10 22h2, Microsoft Windows 11 23h2, Microsoft Windows 11 24h2, Microsoft Windows 11 25h2 and 6 more.
How do I fix CVE-2026-58638?
No fix has been published for CVE-2026-58638 yet. Limit exposure of the affected software until one is available.
Is CVE-2026-58638 being exploited?
There is no known exploitation of CVE-2026-58638 in the wild and no public exploit code.
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-h2wp-qqpw-35j4.