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Fun With Wireshark: Packet Analysis and Ethical Hacking Part 1




This is David Bombal's course on Udemy. Screenshots will be scarcer because, hey, you didn't pay for this. I did. This covers the first 4 sections (Sans the OSI model):

  • Introduction
  • Setting Up
  • Using Filters


Setting Up: 




Setting up Wireshark, and the Npcap setup has an option for "Support raw 802.11 traffic( and monitor mode) for wireless adapters".

It seems like something I'd want to pick, but I will wait and follow the instructions...for now. I could click it, I already set a restore point.

My first thought was untagged VLAN traffic. I don't know enough about WS here to know what it may interfere with.

We now hav Npcap loopback adapter.

Be mindful of where we're telling WS to capture from; check your interfaces.

("Why can't I see http traffic?" ->
https://osqa-ask.wireshark.org/questions/37704/wireshark-not-showing-http-protocols)

"You're probably capturing on a protected network; the 802.11 header isn't encrypted, so Wireshark is able to dissect the encrypted traffic as 802.11 traffic, but the payload is encrypted, so Wireshark can't even dissect it as IP traffic, much less TCP or HTTP, so it shows up as "802.11"."


Ethernet frames are L2.



Those represent the levels of the OSI model from top to bottom - Physical, Data Link, Network, Transport. The last one combines Application, Presentation, and Session. You can open it and see the OS, browser used.

When the source is a server serving a webpage, you can click it and see the page in question the client received (provided it's in cleartext). Very cool.

But what if you're not capturing packets?


Remember; Double check what interface is capturing traffic; Span or Mirror a port on the switch.

Span? Mirror?


ON a Cisco switch:
config t
monitor session 1 source int [interface]
monitor session 1 destination int [int with  monitoring station]





Filters:


When you are using filters, sometimes the bar may turn red. Keep going, it will turn green when you're finished.







These are display filters.

Silly thing; Make sure to hit enter when you've filled out the filter.

Two filtering language

- Capture packets
- Display packets

Primitives: Filtering on a house IP add or name.

Putting in the protocol gives a different output than putting in the display filter (tcp.port == 23)





(Right click a packet and go to Follow > TCP Stream. This doesn't work with every packet)

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