See what sort of trouble users can get in trying to type your domain name. Find lookalike domains that adversaries can use to attack you. Can detect typosquatters, phishing attacks, fraud, and brand impersonation. Useful as an additional source of targeted threat intelligence.
DNS fuzzing is an automated workflow for discovering potentially malicious domains targeting your organisation. This tool works by generating a large list of permutations based on a domain name you provide and then checking if any of those permutations are in use. Additionally, it can generate fuzzy hashes of the web pages to see if they are part of an ongoing phishing attack or brand impersonation, and much more!
In a hurry? There is web version available - try it!
- Variety of highly effective domain fuzzing algorithms
- Unicode domain names (IDN)
- Additional domain permutations using dictionary files
- Efficient multithreaded task distribution
- Live phishing webpage detection
- Rogue MX host detection (intercepting misdirected e-mails)
- GeoIP location
- Export to CSV and JSON format
Python PIP
$ pip install dnstwist
Git
If you want to run the latest version of the code, you can install it from Git:
$ git clone https://github.com/elceef/dnstwist.git
$ cd dnstwist
$ pip install .
OSX
Installation is simplified thanks to Homebrew package:
$ brew install dnstwist
This will install dnstwist along with all dependencies, and the binary will
be added to $PATH.
Docker
If you prefer Docker, you can pull and run official image from the Docker Hub:
$ docker run elceef/dnstwist
This tool is designed to run fine with just standard Python3 library. However, a couple of third-party packages are required to show its full potential.
Debian/Ubuntu/Kali Linux
If running Debian-based distribution, you can install all external libraries with just single command:
$ sudo apt install python3-dnspython python3-tld python3-geoip python3-whois \
python3-requests python3-ssdeep
Alternatively, you can use Python PIP. This can be done within a virtual environment to avoid conflicts with other installations. However, you will still need essential build tools and a couple of libraries installed.
$ sudo apt install libfuzzy-dev
$ pip3 install -r requirements.txt
The tool will run the provided domain name through its fuzzing algorithms and generate a list of potential phishing domains.
Usually thousands of domain permutations are generated - especially for longer
input domains. In such cases, it may be practical to display only registered
(resolvable) ones using --registered argument.
$ dnstwist --registered domain.name
Ensure your DNS server can handle thousands of requests within a short period
of time. Otherwise, you can specify an external DNS server with --nameservers
argument.
Manually checking each domain name in terms of serving a phishing site might be
time-consuming. To address this, dnstwist makes use of so-called fuzzy hashes
(context triggered piecewise hashes). Fuzzy hashing is a concept that involves
the ability to compare two inputs (in this case HTML code) and determine a
fundamental level of similarity. This unique feature of dnstwist can be
enabled with --ssdeep argument. For each generated domain, dnstwist will
fetch content from responding HTTP server (following possible redirects) and
compare its fuzzy hash with the one for the original (initial) domain. The
level of similarity will be expressed as a percentage.
Please keep in mind it's rather unlikely to get 100% match for a dynamically generated web page. However, each notification should be inspected carefully regardless of the score.
$ dnstwist --ssdeep domain.name
In some cases, phishing sites are served from a specific URL. If you provide a
full or partial URL address as an argument, dnstwist will parse it and apply
for each generated domain name variant. This is obviously useful only with the
fuzzy hashing feature.
$ dnstwist --ssdeep https://domain.name/owa/
$ dnstwist --ssdeep domain.name/login
Very often attackers set up e-mail honey pots on phishing domains and wait for
mistyped e-mails to arrive. In this scenario, attackers would configure their
server to vacuum up all e-mail addressed to that domain, regardless of the user
it was sent towards. Another dnstwist feature allows performing a simple test
on each mail server (advertised through DNS MX record) to check which one can
be used for such hostile intent. Suspicious servers will be flagged with
SPYING-MX string.
Please be aware of possible false positives. Some mail servers only pretend to accept incorrectly addressed e-mails but then discard those messages. This technique is used to prevent "directory harvesting attack".
$ dnstwist --mxcheck domain.name
If domain permutations generated by the fuzzing algorithms are insufficient,
please supply dnstwist with a dictionary file. Some dictionary samples with
a list of the most common words used in phishing campaigns are included. Feel
free to adapt it to your needs.
$ dnstwist --dictionary dictionaries/english.dict domain.name
If you need to check whether domains with different TLDs exist, you can use the
--tld option. You'll need to supply the TLDs list in a text file. A sample
file is provided.
$ dnstwist --tld dictionaries/common_tlds.dict example.com
Apart from the colorful terminal output, the tool allows exporting results to
CSV and JSON. In case you want to chain it with other tools and need just the
permutations without making any DNS lookups, use --format idle:
$ dnstwist --format csv domain.name | column -t -s,
$ dnstwist --format json domain.name | jq
$ dnstwist --format idle domain.name
The tool can perform real-time lookups to return geographical location of IPv4
addresses. Use --geoip option to display country name next to each address.
$ dnstwist --geoip domain.name
To display all available options with brief descriptions simply execute the tool without any arguments.
Happy hunting!
Along with the length of the domain, the number of variants generated by the algorithms increases considerably, and therefore the time and resources needed to verify them. It's mathematically impossible to check all domain permutations - especially for longer input domains which would require millions of DNS lookups. For this reason, this tool generates and checks domains very close to the original one. Theoretically, these are the most attractive domains from the attacker's point of view. However, be aware that the imagination of the aggressors is unlimited.
The scanner is utilized by tens of SOC and incident response teams around the globe, as well as independent information security analysts and researchers. On the top of this, it's integrated into products and services of many security providers, in particular but not only: Splunk, RecordedFuture, SpiderFoot, DigitalShadows, SecurityRisk, SmartFense, ThreatPipes, Cortex XSOAR, Mimecast.
To send questions, thoughts or a bar of chocolate, just drop an e-mail at marcin@ulikowski.pl. You can follow the author on Twitter to stay in the loop on major improvements and related news. Any feedback is appreciated. If you have found some confirmed phishing domains or just like this tool, please don't hesitate and send a message. Thank you.