Claude traces the origin of widely used cryptographic curves

Anthropic says Claude has explained a decades-old mystery behind ECDSA, the elliptic-curve standard used across secure web connections, software signing and digital identity systems.

The parameters for the NIST curves were published without a clear account of how their seeds were chosen. That opacity fueled years of suspicion that the numbers might conceal a deliberate weakness. Anthropic’s internal research model instead found that most seeds match output from lrand48, a common pseudorandom generator in 1990s C libraries, initialized with Unix timestamps.

Claude wrote scanners for dozens of generator and output combinations, recognized the generator’s statistical signature, then recovered internal states using lattice techniques. The reconstructed timestamps fall in the period when the curves were being developed. The model also traced several base points to generators used by the Certicom cryptography library.

Anthropic stresses that this is not a cryptographic break or a new attack. The mundane, reproducible generation process makes a hidden backdoor less plausible and increases confidence in the curves. The investigation is not complete: one binary-curve seed and several base points remain unexplained.

The broader signal is that long-running technical mysteries with machine-checkable hypotheses are becoming strong candidates for AI-assisted research.