Is port 109 (POP2) dangerous?

Port 109 is classified as medium risk. It is commonly exposed but consider using encrypted alternatives where available and monitor activity.

Should port 109 be open on my firewall?

Port 109 can be open but should be monitored closely. Keep the service updated and prefer encrypted alternatives where available.

What transport protocol does port 109 use?

Port 109 (POP2) uses the TCP transport protocol and falls under the Email category.

:109 (TCP)

POP2

Medium Risk

TCP — Email

On this page

Port Overview

Port Number 109

Service Name POP2

Transport Protocol TCP

Category Email

Security Risk Medium

Port Range Well-Known (0-1023)

What is Port 109?

POP2 (Post Office Protocol version 2) is the predecessor to POP3, defined in RFC 937. It is completely obsolete; all modern email clients use POP3 (port 110) or IMAP (port 143).

TCP Email

Security Considerations

Port 109 (POP2) is classified as medium risk. While this service is commonly exposed, consider using encrypted alternatives where available.

Recommendation: Keep the service updated. Monitor logs for unusual activity.

POP2

Port Overview

What is Port 109?

Security Considerations

Related Ports — Email

Related Terms