Origin of security certificate

Help
1

My domain is www.colis.cranswick.org.uk running on Krystal Hosting with LightSpeed. I have been running without problems for 6+ years with LetsEncrypt certificates. I have two other websites running off the same domain with LetsEncrypt without problems. I have Edge, Firefox, Chrome and Opera for testing. One user on Virgin Media and using Chrome has suddenly started getting certificate problems.

Chrome is giving its general "Your Connection is Not private" spiel and then saying,
"This server could not prove that it is www.colis.cranswick.org.uk; its security certificate is from *.prod.lg.securingsam.com. This may be caused by a misconfiguration or an attacker intercepting your connection."

securingsam.com appears to be a legitimate site that has just been bought by Qualcomm, so I can't see why it might be involved in an intercept attempt or what relationship it might have to LetsEncrypt.

The problem this user is having is persistent. I have launched the site with Chrome on my PC and there is no problem. Any thoughts would be appreciated.

2

It appears that for some reason your domain is being blocked by a firewall on the user's router.

3

Thanks. I've now got further information from the user, and Virgin Media is saying it has blocked the domain due to malicious content. I presume that is interfering with Chrome trying to verify the security certificate. Still wondering how securingsam.com gets involved.

4

That's best directed to the user having the problem as that is happening at their end. That is probably a service used by their firewall which gets involved in the traffic flows to provide the protection.

The securingsam site has nothing to do with your certs. Certs do not perform any dynamic traffic routing. They are static files sent out by your server.

5

Thanks, that clears that up.