We're seeing Certificate Revocation Lookup Failure errors all of the sudden today. We're seeing the problem occurring across dozens of LetsEncrypt certs hosted in multiple AWS regions and accessed from all over the USA. I'm guessing there's a problem with the CRL/OCSP infrastructure. Anyone else s…

I opened a ticket with Quad9 and it looks like they have resolved the issue. Zachary (Quad9) Oct 19, 2021, 19:04 UTC Hello, Thanks for contacting Quad9 support. We have added *.lencr.org to our permanent allow list. We are pushing the update to all global servers now. If it's not already unbloc…

Are you seeing these CRL failures for this certificate? ISRG Root X1 signed by DST Root CA X3 If so, that's expected since the CRL for DST Root CA X3 is no longer operational.

No, we already went through the Root expiration fiasco. These are all certs that were deleted and issued brand new on Sept 29 2021, and this issue just started today. Cert Chain: R3 Fingerprint SHA256: 67add1166b020ae61b8f5fc96813c04c2aa589960796865572a3c7e737613dfd Pin SHA256: jQJTbIh0grw0/1TkH…

Could you please specify what exact issue you're having? Error messages? Details? Anything?

Office 365 authentication through ADFS Web Application Proxy and also RDP Gateway connections using Let's Encrypt cert are throwing warnings: [image]

And what's the content of "View Certificate"?

It's not a cert issue, just started having problems today. Have one right now where a colleague is seeing an issue but I'm not. Looks like it might be a DNS issue with Quad9 resolving OCSP servers. [1]Authority Info Access Access Method=On-line Certificate Status Protocol (1.3.6.1.5.5.7.48.1) A…

Yep that's the issue. [image] Blocked Domain Tester | Quad9 Check to see if a domain is blocked [image]

I wonder why Mastercard flagged this domain as suspicious. :frowning: Thank you for getting to the bottom of this issue, @RobBiddle .

Certificate Revocation Lookup Failure Oct 19 2021

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Osiris October 19, 2021, 4:59pm 2

NetCraft doesn't show anything weird: Performance Report for r3.o.lencr.org | Netcraft

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Certificate Revocation Lookup Failure Oct 19 2021

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