CeWL on Kali Linux Tools: A Powerful Custom Wordlist Generator
Categories:
5 minute read
Introduction
When it comes to penetration testing, password cracking is an essential component of security assessments. Attackers and ethical hackers alike rely on custom wordlists to increase their chances of successful password discovery. One of the most effective tools for generating these wordlists is CeWL (Custom Word List Generator), a utility included in Kali Linux. This tool is particularly useful for gathering words from a target website and crafting a more context-specific wordlist for password cracking.
In this blog post, we’ll dive deep into CeWL, exploring its functionalities, use cases, and how you can leverage it effectively in your security assessments.
What is CeWL?
CeWL (pronounced “cool”) is a Ruby-based tool developed to scrape text from websites and create custom wordlists. Unlike generic wordlists, which may contain irrelevant words, CeWL helps security professionals generate targeted wordlists based on a specific domain or topic. This makes it highly effective in password-cracking scenarios where users tend to use words related to their organization or interests in their passwords.
CeWL is a part of Kali Linux’s suite of security tools, and it can be used to extract keywords, metadata, and custom words from web pages, helping penetration testers create optimized dictionaries for brute-force attacks.
Installing CeWL in Kali Linux
CeWL comes pre-installed in Kali Linux, but if for some reason it is missing, you can install it using the following command:
sudo apt update && sudo apt install cewl
To verify that CeWL is installed, run:
cewl --help
If the installation is successful, you should see a list of available options and commands.
Basic Syntax and Usage
The basic syntax of CeWL is as follows:
cewl [options] <URL>
For example, if you want to scrape words from a website like example.com, you would run:
cewl http://example.com
This command will return a list of words found on the website.
Advanced Usage of CeWL
CeWL offers a variety of options that make it more powerful for targeted wordlist generation. Here are some key features:
1. Specifying Word Length
By default, CeWL extracts all words, but you may want to filter out shorter words to improve the effectiveness of your wordlist. You can specify a minimum word length using the -m flag:
cewl -m 6 http://example.com
This command will only extract words that are at least 6 characters long.
2. Depth of Crawling
CeWL allows you to specify how deep it should crawl a website. If a site has multiple pages, increasing the depth ensures that more words are gathered. The -d option lets you specify the crawl depth:
cewl -d 2 http://example.com
This command tells CeWL to crawl two levels deep into the website.
3. Output to a File
Instead of displaying words in the terminal, you can save them to a file for later use. The -w flag allows you to specify an output file:
cewl -w wordlist.txt http://example.com
This command saves the extracted words into wordlist.txt.
4. Including Metadata from Documents
CeWL can extract metadata from PDF, DOCX, and other documents available on a website. This can be useful because documents often contain names, project codes, and internal terms that users may use in their passwords. To extract metadata, use the --meta option:
cewl --meta http://example.com
If you need more details, you can enable verbose mode with:
cewl --meta --debug http://example.com
5. Using CeWL with Authentication
Some websites require authentication before allowing access to certain pages. CeWL supports Basic and Digest Authentication, allowing you to access protected pages:
cewl -u username -p password http://example.com
This command allows CeWL to crawl pages that require a username and password.
6. Using CeWL with a User-Agent
Some websites block automated crawlers, but CeWL allows you to specify a custom user-agent to mimic a real browser:
cewl --user-agent "Mozilla/5.0" http://example.com
This can help avoid detection by web servers that restrict automated scripts.
Practical Use Cases for CeWL
CeWL is useful in several scenarios, including:
1. Penetration Testing & Password Cracking
Security professionals can use CeWL to create a customized wordlist based on the target company’s website. This increases the likelihood of cracking passwords using tools like John the Ripper or Hashcat.
2. Social Engineering Engagements
Words extracted using CeWL can be used to craft phishing emails or personalized attacks, making social engineering efforts more convincing.
3. OSINT (Open-Source Intelligence) Gathering
Cybersecurity researchers can use CeWL to collect organization-specific keywords that may be useful in reconnaissance phases.
4. Dictionary-Based Attacks on Encrypted Files
If a user has encrypted a ZIP file, PDF, or any other file with a password, using a CeWL-generated wordlist can improve the chances of successful decryption.
Combining CeWL with Other Kali Linux Tools
CeWL becomes even more powerful when used with other Kali Linux tools. Some examples include:
John the Ripper – Use CeWL to generate a wordlist and then attempt password cracking:
john --wordlist=wordlist.txt hashfileHydra – Use CeWL to create a wordlist for brute-force attacks against SSH, FTP, or web logins:
hydra -L users.txt -P wordlist.txt ssh://192.168.1.1Crunch – Use CeWL wordlists as input for Crunch to generate custom password variations.
Conclusion
CeWL is an incredibly useful and versatile tool for penetration testers, ethical hackers, and cybersecurity professionals. It helps in creating customized wordlists tailored to specific targets, increasing the success rate of password attacks. Whether you’re conducting penetration testing, social engineering, or OSINT research, CeWL is a must-have in your security toolkit.
By combining CeWL with other Kali Linux tools, you can build a more effective security assessment strategy. However, as with all hacking tools, remember to use CeWL responsibly and ethically, ensuring that it is only applied in legal and authorized scenarios.
If you’re looking to strengthen your cybersecurity skills, start experimenting with CeWL today and take your penetration testing capabilities to the next level!
Did you find this guide helpful? Let us know in the comments, and feel free to share your experiences with CeWL!
Feedback
Was this page helpful?
Glad to hear it! Please tell us how we can improve.
Sorry to hear that. Please tell us how we can improve.