I'm currently in the process of becoming PCI compliant and I have 6 warnings remaining. The one I'm particularly struggling with is "SSL Certificate Cannot Be Trusted IMAP (143/TCP)". I'm using Postfix/Courier-Imap on CentOS 6.5 and I have an SSL certificate already installed on port 993 (IMAPS).
My question is, how do I add, edit or remove the SSL on port 143?
I thought that port 993 was IMAP + SSL so I'm not sure why my scanner is complaining about an untrusted SSL on port 143.
Sorry if this isn't very clear.
Update: This issue also occurs on ports 587, 443, 110 and 25 (SSL certificate cannot be trusted) and the description given is "The server's X.509 certificate does not have a signature from a known public certificate authority". Is there a central certificate somewhere that these warnings are referring to?