From charlesreid1

DNS Attacks

So what is DNS anyway?

DNS is domain name resolution protocol - it's how names like "yahoo.com" get turned into IP addresses like "10.20.30.40". It's a fundamental part of the way the internet routing system works, and it makes navigating the web possible - nay, even easy! - for non-machine meatbags.

To perform attacks on DNS traffic, we will, of course, need access to the sheep's traffic. We cannot selectively intercept the sheep's DNS traffic without, well, actually intercepting the sheep's traffic. Therefore, we will need to use a technique to Man in the Middle the sheep before we can proceed to hijack DNS requests.

One such method is ARP Poisoning with Bettercap, which conveniently performs DNS attacks as well.

DNS Hijacking

DNS hijacking consists in an attacker hijacking DNS traffic from the sheep in order to maliciously redirect the sheep to servers of our own choosing.

This is typically achieved at Level 3 and 4 on a network: ARP spoofing to redirect a sheep's traffic through the attacker, and a DNS server to handle requests (to send the sheep to our malicious server) or forward requests on to other DNS servers to take care of. However, it can also be achieved at the physical layer, by modifying the filesystem of a sheep's computer to permanently point to a pirate DNS server.

This type of attack can be carried out with the Bettercap tool. See below or Bettercap#DNS Spoofing.

Current status: failing

Tools

Bettercap

Yep, Bettercap can execute MITM DNS attacks. This consists of two steps:

  • Define your malicious DNS entries
  • Execute your bettercap DNS attack

This will perform DNS spoofing, meaning Bettercap will trick the sheep into sending all of its DNS requests to the attacker instead of to the gateway. This allows the attacker to hijack traffic to certain sites.

When a DNS attack is combined with the HTTP proxy for traffic modification, this allows you to man-in-the-middle a DNS request for a particular domain (say, Microsoft.com), redirect the traffic through the HTTP proxy, and modify either the traffic sent from the sheep to the server, or from the server to the sheep.

See the Bettercap#DNS Spoofing page for more detailed notes.

dnsspoof

You can also MITM attack a sheep's DNS using Dnsspoof, which is part of the Dsniff suite. It is a specialized tool intended solely for DNS spoofing. If you use dnsspoof, you should combine it with another tool like arpspoof or Bettercap to perform an ARP poisoning attack, or use some other technique for gaining control of the sheep's traffic.

EvilFOCA

Windows tool

Link: https://github.com/ElevenPaths/EvilFOCA

Tool for conducting various DNS attacks (and other types of attacks)

  • Capable of conducting DHCP ACK Injection - attacker monitors DHCP exchanges, interferes by sending packets, attacker acts as fake DHCP server
  • DNS Hijacking - hijacking the sheep's DNS channel to control where the sheep's requests point them

Links

Related Pages

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