What is POP3?
POP3 (Post Office Protocol 3) is another email retrieval protocol that downloads messages to your device. It’s older and less feature-rich than IMAP.
Common security issues
Plaintext login credentials.
User enumeration.
Brute-force authentication.
Often enabled by default on mail servers.
Default ports
110 (POP3)
995 (POP3S – secure)
Enumeration
Enumerate POP3 via banners, CAPA, NTLM, and auth checks
Vulnerability Discovery
Guides for finding POP3 auth weaknesses and TLS misconfigs
POP3 Weak Authentication Testing
Exploitation
Brute force POP3 logins and harvest mailbox data post-auth