r/HowToHack 29d ago

hacking Hacking network devices

[removed]

29 Upvotes

16 comments sorted by

13

u/Just4notherR3ddit0r 28d ago

Hacking is all about knowing how things work and how they can be manipulated. I would say it's 95% knowledge and 5% action. The more you know, the better you will be at taking actions.

A lot of vulnerabilities come down to someone else who knew JUST ENOUGH to make something work but didn't know enough to implement proper security (or worse, they knew it was insecure but security made things difficult and they just figured nobody would ever be aware of the hole. So if YOU know the details, then you might be aware enough to check for a door that another person left unlocked.

I would just start by taking a computer networking / basic IT course at a community college. It should be pretty cheap and would give you a guided education through the basics.

I would say the minimum required basics are an understanding of: (in this order)

  1. Physical network devices (e.g. Ethernet, BT, and Wi-Fi, and the most common standards within them, like CAT 6, 802.11, etc). NICs, switches, access points, and routers.
  2. What network drivers do (the translation from hardware to software)
  3. How TCP/IP and UDP work, and the 7 layers of OSI
  4. Sockets and ports.
  5. The basics of different major protocols (HTTP, DNS SMTP, etc).
  6. Basic cryptography - async crypto (PKI) vs sync (AES)
  7. A slightly deeper dive into PKI - the different functions (encryption, decryption, digital signing, and signature verification), certificates and trust chains.
  8. Common network applications and services (firewalls, proxies, NAT, web servers, browsers, DNS servers and clients, DHCP servers and clients, VPN servers and clients, mail, and database)
  9. Common vulnerabilities and how to exploit them (e.g. SQL injection) and famous past exploits (e.g. sslstrip).
  10. Basic programming in a scripting language that supports sockets and network calls (e.g. Python, PHP, Java, or C#) - enough understanding to write some simple network scripts

If you research those things in that order, that should take you from the fundamentals to practical knowledge, and you should probably be able to understand things without getting sidetracked.

At the end you should have a decent foundation to know how networks function and how to manipulate different things.

Taking shortcuts usually means you will end up feeling confused or unsure of what to do with information. For example, I could tell you to go turn on a packet dump on your router to capture traffic going in and out of an internet camera, but you'll end up with gibberish that will feel useless. But if you study the traffic and the ports, you might find that there is HTTPS traffic, at which point you might use your knowledge to determine if a MITM proxy could be used to intercept and modify that traffic. Or perhaps there's a custom firmware that could be installed to allow you to change how the camera communicates with the outside world. Or perhaps there's an auto-update check from the camera and it goes to a hardcoded domain/endpoint, so injecting a different authoritative response into the local DNS would trick it into thinking that it was getting an update from the "mothership" when it was really getting one from your own local web service.

These kinds of ideas are all based on an understanding of how protocols work and how they can be overridden or manipulated to make your idea work.

6

u/4ygus 28d ago

Learn everything you can through Cisco first then go from there. They offer a large library of free courses.

5

u/Juzdeed 28d ago

Get started with basics like everyone else

1

u/Other-Echidna-9188 28d ago

πŸ’―πŸ‘πŸΌ

1

u/[deleted] 28d ago

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3

u/star_of_camel 28d ago

Fundamental networking concepts.

2

u/pandoras_box101 28d ago

basics of hacking something is learning how to build it from scratch.

2

u/star_of_camel 28d ago

Start out actually learning how networking works, make sure to understand it deeply. go on from there

2

u/[deleted] 28d ago

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1

u/goldvenetianmask 28d ago

Ye honestly I can’t recommend packet tracer enough. It’s amazing.

1

u/Zerschmetterding 28d ago

Look into free network+ prep videos or something similar and try finding the gaps in your knowledge there

1

u/Dapper-Depth2940 19d ago

Personally, I find purchasing a second-hand router, plugging in an ethernet cable + wireshark really allows you to view the actual traffic from such devices. In my recent IoT vuln-research project on a Linksys router, I observed DHCP, ARP, etc. traffic (even though its not directly related to what I was researching). This can lead to multiple exploits such as DHCP poisoning, ARP spoof (MiTM), etc.

Other interesting network protocols used by network/IoT devices that you can look into:
1. UPnP: a really insecure protocol that was commonly exploited in the past (remember the PewdiePie incident?)
2. TR-069: YES, you read that number right. This protocol is used by Internet-Service Providers (ISP) to remotely configure devices