Let's Encrypt certificate false positive on F-Secure Freedome VPN

Let’s Encrypt certificate appears as a false positive threat on F-Secure Freedome VPN.

I received a report from a user of F-Secure Freedome VPN on OSX Yosemite, 10.10.5. that she cannot access my website (https://relay70.metatron.ai.) The VPN blocks the website as insecure. I reported the problem to the vendor (F-Secure) too.

On the vendor side the issue is tracked as the following:

Number: 00758968                                                                    
Created: 2016-04-26                                                                 
Subject: VPN identifies Let's Encrypt certificates as a threat

I wonder if other Let’s Encrypt users have similar experience or if the Internet Security Research Group can liase with F-Secure about the issue.

Thanks for your consideration,

In solidarity,


I’m curious as to how this pans out with F-secure. The only press I’ve seen from them regarding Let’s Encrypt so far was quite positivie: https://de.business.f-secure.com/boesartige-werbung-nutzt-ssl-zertifikate-von-lets-encrypt/

Are you sure the ceritifcate is the problem?

Could just be an Honest Mistake™

Maybe it’s because of the poor configuration?

Right, we should test more. Is there a canonical URL with a Let’s Encrypt certificate to test against?