Anti-bot systems can fingerprint browsers by exploiting subtle differences in floating-point math implementations across operating systems, such as discrepancies in the last bits of `Math.tanh()` results. This technique leverages the fact that glibc, Apple's libsystem_m, and Windows UCRT produce slightly different outputs for the same mathematical inputs, creating a unique hardware-software signature.
Background
Browser fingerprinting is a common method used by websites to identify and track users without cookies, often relying on canvas or WebGL data. This article introduces a less obvious vector based on low-level numerical precision differences inherent to specific OS math libraries.
- Source
- Lobsters
- Published
- Jul 13, 2026 at 07:06 AM
- Score
- 7.0 / 10