NNTP 119

Banner Grabbing with Netcat

To grab the banner of an NNTP service on port 119, you can use nc (Netcat) with the following command:

nc -nvC 10.11.1.72 119 HELP LIST

• -nvC:

  • -n: No DNS resolution, connects using IP.

  • -v: Verbose mode to see the connection details.

  • -C: Enable CRLF line endings (necessary for NNTP communication).

Command Breakdown:

• HELP: Sends the HELP command to the NNTP server to fetch a list of supported commands or a banner.

• LIST: Can request a list of newsgroups available on the server.

If the server is responsive, it will return a list of commands or information about the service.

2. NNTP over TLS (Port 563)

To test NNTP over a secure connection (using TLS), you can use openssl s_client on port 563:

openssl s_client -crlf -connect 10.0.0.3:563

• -crlf: Sends carriage return and line feed (CRLF) characters as per the NNTP protocol.

• -connect 10.0.0.3:563: Connects to the target server on port 563 (NNTP over TLS).

This will establish a secure connection to the server. After connecting, you can issue NNTP commands (like HELP or LIST) to interact with the server securely.