Claude solves 26-year nsa elliptic curve seed mystery in under 30 minutes

Anthropic announced on October 16, 2026, that its Claude model identified the origins of the seeds used to generate five NIST-standard elliptic curves in under 30 minutes. These curves, part of the U.S. digital signature standard since 2000, were suspected of containing NSA-backed backdoors due to the lack of transparency in their seed generation process. The model traced the seeds back to the C library’s lrand48 pseudorandom number generator, initialized with Unix timestamps from 1997 to 1998. P-256’s seed, for instance, was the 1,842nd candidate generated on August 16, 1997. Anthropic emphasized that this does not break ECDSA or reveal new attack vectors, but it reduces concerns about intentional backdoors. The research, however, does not fully explain the origin of the B-163 seed, the generation method of some base points, or why certain candidate curves were skipped.