Secure Boot expired in June and nothing broke. That is the problem
On 24 and 27 June, two of the certificates Microsoft has used to sign the boot chain since 2011 expired. Not a single machine went down: Microsoft states plainly that the device keeps starting and updating normally. What stops is something else — revocations, the boot manager, early-boot mitigations — and it raises no alert at all. A third date is still open: 19 October. How to check in two minutes whether your Windows estate, your Linux servers and — this is the one nobody looks at — your virtual machines already carry the 2023 certificates.
Microsoft 365
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