Port 143 — IMAP

TCP · Port 143/TCP is used for the Internet Message Access Protocol (IMAP), a protocol that allows email clients to access and manage email messages on a mail server. IMAP enables users to search, retrieve, and delete emails remotely. This port/service is critical in modern email communication, as it provides secure access to email accounts.

Port Number: 143
Service Name: IMAP
Protocol: TCP
Common Software: Dovecot, Cyrus IMAP

Security Notes

Review IANA registry for port 143 usage. Apply principle of least privilege - only open ports that are required.

FAQ

What is port 143 used for?

Port 143 is used for IMAP. Port 143/TCP is used for the Internet Message Access Protocol (IMAP), a protocol that allows email clients to access and manage email messages on a mail server. IMAP enables users to search, retrieve, and delete emails remotely. This port/service is critical in modern email communication, as it provides secure access to email accounts. Common software: Dovecot, Cyrus IMAP.

Is port 143 dangerous to leave open?

Review IANA registry for port 143 usage. Apply principle of least privilege - only open ports that are required.

How do I check if port 143 is open?

Use nmap: nmap -p 143 <target> or check locally: ss -tlnp | rg 143