CVE-2026-58638 Microsoft CVE debrief

Who should care

System administrators and security teams responsible for Windows-based systems, especially those using Windows 10, Windows 11, and Windows Server, should be aware of this vulnerability and take appropriate action to patch or mitigate it.

Technical summary

The vulnerability is caused by a missing cryptographic step in the Windows Boot Loader, allowing an authorized attacker to bypass a security feature locally. The Common Vulnerability Scoring System (CVSS) score for this vulnerability is 6.0, indicating a medium severity. The CVSS vector is CVSS:3.1/AV:L/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:N. This issue affects multiple versions of Windows 10, Windows 11, and Windows Server.

Defensive priority

Medium priority should be given to patching this vulnerability, as it could allow an authorized attacker to bypass a security feature locally.

Recommended defensive actions

• Apply the patch provided by Microsoft
• Review and update system configurations to ensure the security feature is properly implemented
• Monitor system logs for potential exploitation attempts
• Review compensating controls for exposed systems while remediation is scheduled and verified
• Check relevant monitoring, detection, and logs for exposed assets that need extra review

Evidence notes

The CVE record was published on 2026-07-14T18:18:46.137Z and has not been modified since. The NVD entry is currently Analyzed. Microsoft has provided a patch for this vulnerability. The vulnerability has a medium severity with a CVSS score of 6.0, indicating that an authorized attacker could bypass a security feature locally.

Official resources