deny telnet command but permit JDBC protocol

Reply
L0 Member

deny telnet command but permit JDBC protocol

We have an internal discussion about whether it is possible to block the 3 way hanshake TCP but allow the JDBC application protocol.
In other words we would like to block the test of the port with the command "telent address port" but we would like that the connections via JDBC continue to work.
is it possible to do this theoretically? Is it possibile to do it wiht paloalto firewall?
Please note: when I say blocking, I mean "connection refused" or "timeout". I do not intend to terminate the connection immediately.

L0 Member

Re: deny telnet command but permit JDBC protocol

if it is possible, could you explain to me how technically it happens?
The "telnet address port" command performs only the TCP handshake. So the packages do not contain any information about the application protocol that you want to use.
How can a firewall make assumptions and deny to initialize tcp protocol?

Highlighted
L7 Applicator

Re: deny telnet command but permit JDBC protocol

Hello,

Remember the PAN needs to let traffic pass so it can identify the App-id. You might try and block the telnet application and see if that works. But blocking the tcp3way is not advised as it will not allow any traffic that is tcp.

 

https://docs.paloaltonetworks.com/pan-os/8-0/pan-os-admin/app-id/app-id-overview.html

 

Regards,

Like what you see?

Show your appreciation!

Click Like if a post is helpful to you or if you just want to show your support.

Click Accept as Solution to acknowledge that the answer to your question has been provided.

The button appears next to the replies on topics you’ve started. The member who gave the solution and all future visitors to this topic will appreciate it!

These simple actions take just seconds of your time, but go a long way in showing appreciation for community members and the Live Community as a whole!

The Live Community thanks you for your participation!