DNSValidator

Forked from https://github.com/vortexau/dnsvalidator.

This version is much less feature rich than the original. However, it doesn't look like the original is being maintained & there is a possibility that it will not return an output (see: vortexau/dnsvalidator#27)

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Table of Contents:

1. What does this do?
2. How do I get it?
   • GitHub
   • Docker
3. How do I use it?
   • CLI
   • Docker
4. You should know.

What does this do?

DNSValidator's approach is different to other DNS query validation tools. This tool performs multiple validation steps on each resolver:

• Baselines non-geolocated domain names against "trusted" public DNS resolvers i.e. 1.1.1.1 (Cloudflare), 8.8.8.8 (Google), and 9.9.9.9 (Quad9)
  • For each resolver being tested DNS Validator ensures that each baseline domain name resolves to the same IP Address.
  • Servers that return an answer that differs from the baseline are immediately skipped
• Performs DNS lookup of known commonly spoofed DNS addresses to ensure NXDOMAIN is returned when expected.
  • Resolvers that do not return NXDOMAIN for random subdomains of known bad target domains are immediately skipped.

How do I get it?

GitHub

❯ git clone https://github.com/frost19k/DNSValidator.git ./dnsvalidator
❯ cd ./dnsvalidator
❯ pip3 install .

Docker

Pull from Docker Hub

❯ docker pull frost19k/dnsvalidator

Build it yourself

❯ git clone https://github.com/frost19k/DNSValidator.git ./dnsvalidator
❯ cd ./dnsvalidator
❯ docker buildx build -t dnsvalidator .

How do I use it?

CLI

Argument	Description
-i, --input-file	File containing Public DNS Servers (Default: public-dns.info)
-o, --output-file	Output file name (Default: "./resolvers.txt")
-r, --root-domain	Root domain to validate against (default: bet365.com)
-t, --threads	Number of concurrent threads (Default: 2)
-v, --verbose	Print additional error messages
-q, --quiet	Do not print banner or error messages

❯ dnsvalidator -i nameservers.txt -o myResolvers.txt -t 12

Docker

❯ docker run -it --rm -v "${PWD}":"/output" frost19k/dnsvalidator -t 12

You should know

• Only IPv4 DNS Resolvers are validated at the current time. IPv6 resolvers are skipped.

• WARNING: Keep the thread count at a reasonable level and/or use a VPS/VPN appropriately. Pushing the thread count too high will give the impression that you are attempting to attack DNS servers, resulting in network level DNS blocks from your ISP.