CeWL (Custom Word List Generator) is a ruby application used to create custom word lists for password cracking or other security testing purposes. It works by extracting potential passwords from a given website and generating a list of unique words and phrases.
Here's a breakdown of CeWL's functionalities:
Website Crawling:
- Target selection: You specify the URL of the website you want to crawl.
- Depth control: You can choose how deep the crawler should go within the website's structure, limiting the number of links it follows.
- External link handling: You can decide whether to follow external links (links leading to other domains) during the crawling process.
Word Extraction and Processing:
- Extracting words: CeWL extracts all words of a certain length (usually three characters or more) from the website's content, including titles, headings, text paragraphs, and even comments within the HTML code.
- Filtering and processing: The extracted words are then filtered to remove common words, punctuation, and other irrelevant characters. Additionally, CeWL can apply various processing techniques, such as converting all letters to lowercase, adding numbers or special characters, and performing basic transformations (e.g., "password" becomes "p@ssw0rd").
Output and Customization:
- Word list generation: The final output is a text file containing the generated custom word list, consisting of unique and potentially relevant passwords based on the information extracted from the website.
- Customization options: CeWL offers various options to customize the word extraction process, such as specifying the minimum word length, defining excluded words or patterns, and choosing the output format (e.g., plain text, specific password cracking tool format).
Ethical Considerations:
- Permission required: Using CeWL to crawl and extract words from a website without explicit permission from the owner is illegal and unethical. It can be considered a violation of their terms of service and potentially data privacy laws.
- Malicious use: The generated word lists could be misused for malicious purposes like brute-force attacks against unauthorized systems or websites.
Overall, CeWL can be a valuable tool for security professionals with proper authorization. It can be used for various purposes, including:
- Penetration testing: Identifying potential password weaknesses in web applications by testing them with custom word lists generated from the website itself.
- Social engineering simulations: Creating realistic password guesses based on the information found on a target's social media profiles or other online presence.
- Security awareness training: Demonstrating the importance of strong passwords by showing how easily weak passwords derived from personal information can be cracked.
However, it's crucial to remember that CeWL is a powerful tool that should be used responsibly, ethically, and in accordance with all legal and ethical frameworks to avoid any misuse.