What is CVE-2026-21265?

CVE-2026-21265 is a security advisory published by Microsoft Security Response Center (MSRC) with High severity. Secure Boot Certificate Expiration Security Feature Bypass Vulnerability

Which CVE IDs does CVE-2026-21265 cover?

CVE-2026-21265 covers the following CVE IDs: CVE-2026-21265. Each CVE has its own detail page on EchelonGraph Pulse with the synthesized EG score.

What is the CVSS v3 score of CVE-2026-21265?

CVE-2026-21265 has a CVSS v3 base score of 6.4, published by Microsoft Security Response Center (MSRC).

CVE-2026-21265HighCVSS 6.4

Secure Boot Certificate Expiration Security Feature Bypass Vulnerability

Vendor

Microsoft Security Response Center (MSRC)

Published

June 2, 2026

Last Modified

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🔗 CVE IDs covered (1)

CVE-2026-21265 →

🔗 CVE IDs covered (1)

📋 Description