Claude cracks 25-year NIST curve seed mystery in 30 minutes: lrand48 plus Unix timestamps
机器之心 · wechat · 2026-10-17
An Anthropic employee handed an internal research model a puzzle that stumped cryptographers for 25 years: in under half an hour, with no hints, Claude traced the origins of NIST's five elliptic curve seeds (P-192 through P-521) — they came from the C library's weak lrand48 PRNG seeded with Unix timestamps, clustered between May 1997 and April 1998.
Method: Claude scanned 34 RNG/output combinations, spotted all-zero high bits characteristic of lrand48, brute-forced hidden bits, and used LLL lattice reduction on truncated outputs — all 10 recovered 48-bit states exactly regenerate the 160-bit seeds. The finding doesn't break ECDSA, but the reproducible generation process reduces the odds of intentionally backdoored curves. The $36,864 bounty goes to the Internet Security Research Group. Some curves' seeds and base points remain unexplained.
Related event: Claude Cracks Decades-Old ECDSA Curve Seed Mystery in Under 30 Minutes(27 posts)→
More from Safety
- Kelsey Tuoc: AI transparency via independent audits and whistleblower protection is essential — S_OhEigeartaigh · 2026-10-18
- OpenCode confirms breach, stolen customer API keys already incurring charges — jedisct1 · 2026-10-18
- SpaceX rep declines to reveal AI safety team size at NYC council hearing — RebeccaBellan · 2026-10-18
- Deep Hat, formerly WhiteRabbitNeos, targets offensive security tasks other AI avoids — hey_abusiddik · 2026-10-18
- Discord desktop RCE disclosed, but the $5k bounty draws security community backlash — rez0__ · 2026-10-18
- Pangram AI detector flags human-written paragraphs, sparking author fears — ArkhamDreamerZero · 2026-10-18