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1098 articles · 101864 vulns · 38/41 feeds (7d)
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6.4
CVE-2026-21265PATCHED
microsoft · windows_10_1607

Windows Secure Boot stores Microsoft certificates in the UEFI KEK and DB. These original certificates are approaching expiration, and devices containing affected certificate versions must update them

Description

Windows Secure Boot stores Microsoft certificates in the UEFI KEK and DB. These original certificates are approaching expiration, and devices containing affected certificate versions must update them to maintain Secure Boot functionality and avoid compromising security by losing security fixes related to Windows boot manager or Secure Boot. The operating system’s certificate update protection mechanism relies on firmware components that might contain defects, which can cause certificate trust updates to fail or behave unpredictably. This leads to potential disruption of the Secure Boot trust chain and requires careful validation and deployment to restore intended security guarantees. Certificate Authority (CA) Location Purpose Expiration Date Microsoft Corporation KEK CA 2011 KEK Signs updates to the DB and DBX 06/24/2026 Microsoft Corporation UEFI CA 2011 DB Signs 3rd party boot loaders, Option ROMs, etc. 06/27/2026 Microsoft Windows Production PCA 2011 DB Signs the Windows Boot Manager 10/19/2026 For more information see this CVE and Windows Secure Boot certificate expiration and CA updates.

Affected Products

VendorProductVersions
microsoftwindows_10_1607< 10.0.14393.8783, < 10.0.14393.8783, < 10.0.17763.8276, < 10.0.17763.8276, < 10.0.19044.6809, < 10.0.19044.6809, < 10.0.19044.6809, < 10.0.19045.6809, < 10.0.19045.6809, < 10.0.19045.6809, < 10.0.22631.6491, < 10.0.22631.6491, < 10.0.26100.7623, < 10.0.26100.7623, < 10.0.26200.7623, < 10.0.26200.7623, < 10.0.14393.8783, < 10.0.17763.8276, < 10.0.20348.4648, < 10.0.25398.2092, < 10.0.26100.32230

References

  • https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-21265(Vendor Advisory)

Related News (2 articles)

Tier B
CERT-FR14h ago
Expiration de certificats Secure Boot en juin 2026 (02 avril 2026)
→ No new info (linked only)
Tier C
CrowdStrike Blog1d ago
Falcon for IT Supports Windows Secure Boot Certificate Lifecycle Management
→ No new info (linked only)
CVSS 3.16.4 MEDIUM
VectorCVSS:3.1/AV:L/AC:H/PR:H/UI:N/S:U/C:H/I:H/A:H
CISA KEV❌ No
Actively exploited❌ No
Patch available
10.0.14393.878310.0.17763.827610.0.19044.680910.0.19045.680910.0.22631.649110.0.26100.762310.0.26200.762310.0.20348.464810.0.25398.209210.0.26100.32230
CWECWE-1329
PublishedJan 13, 2026
Last enriched19h ago
Trending Score33
Source articles2
Independent2
Info Completeness9/14
Missing: epss, kev, exploit, iocs, mitre_attack

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Verification

State: verified
Confidence: 100%

Vulnerability Timeline

CVE Published
Jan 13, 2026
Patch Available
Jan 14, 2026
Discovered by ZDM
Apr 1, 2026