● Covered by 1 source · 1 reportMedium impact
Chrome 148 Introduces OS Fingerprinting via Math.tanh Changes
Key points
- Math.tanh now varies by OS in Chrome 148 and later versions.
- Distinct outputs create potential for browser fingerprinting.
- Previous versions (Chrome 147 and earlier) did not leak this information.
Change in Math.tanh Implementation
With Chrome 148, the implementation of Math.tanh was changed to use standard libraries based on the OS environment. Prior to this version, a bundled function produced identical results across different operating systems, preventing OS-specific identification.
Operational Differences Across OS
Different operating systems implement the Math.tanh function using their respective libraries: Linux uses glibc, macOS uses Apple’s libsystem_m, and Windows uses UCRT. This results in varying numerical outputs for the same input across different systems, making it possible for detectors to classify browsers by their OS.
Impact on Privacy and Fingerprinting
The change increases the feasibility of OS fingerprinting techniques, which can track users more effectively. Each OS produces a distinct output for certain Math.tanh inputs, providing a unique signature that could be used alongside other fingerprinting methods.
Relevance to Browsers and Detecting Technologies
Scrapfly and similar technologies may need to adapt to these new variations in Math outputs to accurately match browser profiles across different systems. As such, this change is significant within the context of browser fingerprinting and user privacy concerns.
✨ This summary was generated by AI from the outlets' reporting listed below. It is not independently verified and may contain errors — check the original sources. How BrevFeed works →
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Reporting from
Starting with Chrome 148, the Math.tanh function provides distinct outputs based on the operating system, enabling fingerprinting. This change allows techniques to classify the OS based on floating-point calculations, introducing privacy implications for users.