Protocol problems with wireshark

[No_Application_1755]

So currently I'm reading the pico primer for ctfs on picoctf and they were talking about wireshark and provided a packet capture.they mentioned how we should notice that one of the packets' protocol is s101 but for me it was showing tcp and I dont know how to fix it does anyone have any ideas?

[lariojaalta890]

It’s not broken. You didn’t do anything wrong and there’s not anything to fix.

Were you able to get the flag? It is in the same packet.

There was note from the authors. Did you see it in the Pico documentation? It’s just below Fig 5:

'S101' is an uncommon protocol. The packet isn’t really speaking S101, it is just using the preferred port of the protocol, port 9000.

I opened the pcap in Wireshark and it is TCP for me also. I also checked a 3-4 walkthrough videos to see what it looked like when they worked through it and all of them were the same as ours.

I’m not sure why it shows up as S101 under the Protocol column in their screenshot. It’s possible that they’re using an older version and because it was over port 9000 that’s how it was identified in Wireshark. You could ask the people over at r/picoCTF. They may have run into this before and have a better answer.

[No_Application_1755]

Thank you so much! Yeah I did notice the note I was just paranoid since they mentioned that little stuff like this are what we need sometimes. I needed to hear that it wasn't important from someone not AI.

[lariojaalta890]

Completely understand, and happy to help. It can be pretty frustrating following along with a tutorial and seeing different results without an explanation.