Vulnerability record

CVE-2026-21265

A permanent, source-backed tracker page. Values are shown only when returned; explicit gaps and read failures remain different states.

Full record read. Reported values and explicit gaps below come from the tracked record. Tracker snapshot: Aug 9, 2026.

What it is

Reported

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.… Source description excerpt; complete tracked detail loads below.

NVD published: Jan 13, 2026 · Source record updated: Aug 9, 2026 · Tracker snapshot: Aug 9, 2026

What is affected

Reported

Microsoft — Windows 10 Version 1809 for 32-bit Systems. Product-level identification only; no affected-version conclusion is available from this field.

NVD published: Jan 13, 2026 · Source record updated: Aug 9, 2026 · Tracker snapshot: Aug 9, 2026

Urgency and basis

Reported

Track · 122.9

Tracker decision tier from the evidence detailed below · Source record updated: Aug 9, 2026 · Tracker snapshot: Aug 9, 2026

Exploitation evidence

Not reported

Not reported by tracked sources.

What to do

Reported

A source remediation link is available. Validate that guidance against the affected product and your environment.

Source remediation ↗

Tracked source remediation field · Source record updated: Aug 9, 2026 · Tracker snapshot: Aug 9, 2026

Evidence detail

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