Skip to content
HackIndex logo

HackIndex

IMAP
Service

IMAP

Email access protocol syncing messages with server.

:143 :993 4 guides 3 phases
1 min read Updated: Jul 13, 2026

What is IMAP?

IMAP (Internet Message Access Protocol) lets mail clients read and sync email from a server. Unlike POP3, it keeps mail on the server so that multiple devices can see the same inbox.

Common security issues

  • Sending credentials in cleartext (without TLS).

  • Weak or reused passwords.

  • Brute-force login attacks.

  • Mailbox enumeration.

  • Improper SSL/TLS configuration.

Default ports

  • 143 (IMAP)

  • 993 (IMAPS – secure)

Enumeration

Enumerate IMAP capabilities, auth methods, and NTLM info

1

Vulnerability Discovery

Guides for testing weak IMAP auth and cleartext credential risks

1

Exploitation

Brute force IMAP logins and harvest mailbox data after access

2