CreepJS

What is CreepJS?

CreepJS is a sophisticated, open-source browser fingerprinting tool designed to shed light on weaknesses and privacy leaks in modern anti-fingerprinting extensions and browsers. Created by abrahamjuliot in June 2020, this project has quickly gained popularity, amassing over 1,500 stars on GitHub.

At its core, CreepJS aims to detect and ignore JavaScript tampering, particularly focusing on prototype lies. It also fingerprints lie patterns, extension codes, and browser privacy settings. What sets CreepJS apart is its use of large-scale validation to collect inconsistencies and its ability to fingerprint new APIs that contain high entropy.

However, it's crucial to note that while CreepJS performs many deep fingerprinting techniques, many of them are highly artificial. This means there's a very low chance of these techniques being used by major platforms in real-world scenarios. As such, CreepJS should be viewed more as a research project showcasing different potential leaks from your browser rather than a definitive tool for assessing real-world fingerprinting risks.

Key Features of CreepJS

CreepJS offers a range of advanced features for fingerprinting and privacy analysis:

1. JavaScript Tampering Detection: The tool can identify attempts to modify JavaScript behavior, particularly focusing on prototype lies.

2. Extension Fingerprinting: CreepJS can detect and fingerprint various privacy-enhancing browser extensions.

3. Browser Privacy Settings Analysis: The tool examines browser configurations to identify privacy-related settings.

4. High Entropy API Fingerprinting: CreepJS can detect and fingerprint new APIs that provide significant identifying information.

5. Bot Detection: The tool includes features to identify automated browsing behavior.

CreepJS as a Research Tool

It's important to understand CreepJS's position as a research tool rather than a representation of typical fingerprinting practices:

1. Artificial Techniques: Many of the fingerprinting methods used by CreepJS are highly sophisticated and may not be employed by most websites or platforms.

2. Comprehensive Approach: CreepJS aims to explore theoretical vulnerabilities, going beyond what's practically used in real-world scenarios.

3. Educational Value: The project serves as an excellent resource for understanding potential browser leaks and privacy vulnerabilities.

4. Cautionary Use: Users should be cautious about relying entirely on CreepJS results when assessing their online privacy, as it may present an overly pessimistic view.

Practical Applications of CreepJS

Despite its research-oriented nature, CreepJS can be valuable for several groups:

1. Privacy Researchers: Those studying browser fingerprinting techniques and privacy vulnerabilities can use CreepJS to explore theoretical limits of fingerprinting.

2. Security Professionals: CreepJS can help identify potential security risks related to browser configurations and extensions, even if some are not currently exploited.

3. Web Developers: Developers can use CreepJS to understand how their websites might interact with various privacy-enhancing technologies and potential future fingerprinting techniques.

4. Privacy-Conscious Users: While results should be taken with a grain of salt, privacy-aware individuals can use CreepJS to gain a deeper understanding of potential browser leaks.

Conclusion

CreepJS represents a significant contribution to the field of browser fingerprinting research. As an open-source project with substantial community interest, it provides valuable insights into potential privacy vulnerabilities in modern browsers and anti-fingerprinting tools.

However, users should approach CreepJS with an understanding of its nature as a research tool. Many of its techniques are highly sophisticated and may not reflect current real-world fingerprinting practices. While it's an excellent resource for exploring theoretical vulnerabilities, it shouldn't be used as the sole basis for assessing one's online privacy.

Ultimately, CreepJS serves as a reminder of the complex landscape of online privacy and the ongoing need for robust, privacy-preserving technologies. Its open-source nature invites collaboration and continuous improvement, contributing to the broader conversation about digital privacy and security.