Anthropic’s internal research version of Claude has resolved a cryptographic puzzle that had lingered for more than two decades, identifying how five widely used NIST elliptic curve seed values were originally generated. The discovery addresses longstanding speculation that the US National Security Agency may have chosen the parameters to create hidden weaknesses in the Elliptic Curve Digital Signature Algorithm (ECDSA).
The curves involved — P-192, P-224, P-256, P-384, and P-521 — were standardized in NIST’s 2000 Digital Signature Standard, but the agency provided no explanation of how their seeds had been selected. For years, researchers suspected a possible backdoor, with one anecdote suggesting the seeds came from hashing a phrase along the lines of “Give Bob and Jerry a raise.” That theory remained unproven, especially after longtime NSA mathematician Jerry Solinas died in 2023.
According to Anthropic’s findings published on October 16, Claude needed less than 30 minutes to trace the seeds to lrand48, a standard pseudorandom number generator from 1990s C libraries that had been initialized with a Unix timestamp. The model detected statistical signatures in the published seeds, then used the Lenstra–Lenstra–Lovász lattice-reduction algorithm to recover the generator’s internal state. The recovered starting values were Unix timestamps between May 1997 and April 1998. For P-256, the seed corresponded to the 1,842nd candidate from a run that began at 01:52:34 UTC on 16 August 1997.
Anthropic also found that base points for P-192 and several ANSI X9.62 example curves were produced using the FreeLIP arithmetic library’s random-number generator, seeded with small integers such as 20,000. The company published short, reproducible code so outside researchers can verify the results. The discovery does not break ECDSA or reveal any new attack; instead, the ordinary generation process makes an intentional search for weakened curves substantially less plausible. Some questions remain unresolved, including the origin of the B-163 seed and the precise selection of certain later base points.
Ripple Head of Engineering J. Ayo Akinyele praised the finding as remarkable, noting that artificial intelligence had resolved a technical mystery through relatively straightforward calculations. He suggested similar techniques could be used for other unresolved cryptographic questions. The $36,864 bounty associated with the seeds is being donated to the Internet Security Research Group, the nonprofit behind Let’s Encrypt.
