Implementation and configuration issues

 Validity dates

 Wrong certificate type

 Revoked certificates

 Incorrect name

 Chain issues

  Invalid root or intermediate CAs

  Self-signed

 Weak signing algorithm

 Weak cipher suite

 Incorrect permissions

 Cipher mismatches

 Downgrade

Keys

 Mismatched

 Improper key handling

 Embedded keys

 Rekeying

 Exposed private keys

 Crypto shredding

 Cryptographic obfuscation

 Key rotation

 Compromised keys