Anthropic Claude Reveals NSA Curve Seed Origins, Reducing Backdoor Concerns
An AI model solved a 25-year mystery regarding NIST elliptic curve parameters, showing they used a standard random number generator rather than hidden inputs.
Key points
- Anthropic's Claude identified that NIST curve seeds originated from the lrand48 generator.
- The finding reduces suspicion of deliberate backdoors in widely used digital signature algorithms.
- The analysis covered five NIST curves and five ANSI X9.62 example seeds.
Anthropic’s Claude model determined that the mysterious seeds behind NIST’s standard elliptic curves came from a simple C random number generator, according to Cyber Security News. This discovery addresses a 25-year-old question about how these critical cryptographic parameters were selected, reducing the likelihood of intentional backdoors. The model completed the analysis in under 30 minutes, providing clarity on the origins of values used in ECDSA digital signatures.
How it unfolded
- NIST standardized ECDSA curves in 2000, but the NSA provided seeds without explanation, fueling backdoor suspicions.
- Former NSA employee Jerry Solinas suggested the seeds were hashes of humorous phrases, which proved incorrect.
- Anthropic’s Claude analyzed the seeds in October 2026, identifying them as outputs from lrand48 initialized with timestamps.
Who is affected
The findings impact trust in NIST curves P-192, P-224, P-256, P-384, and P-521, which are foundational to digital signature verification. According to Cyber Security News, services relying on these standards, such as Apple’s iMessage protocol using P-256, benefit from this historical clarification. The resolution helps explain why trust in curve selection matters for widely used security services.
The fix
No software patch or update is required for this finding, as it concerns the historical origin of public parameters rather than a vulnerability in implementation. Anthropic donated the $36,864 bounty associated with the mystery to the Internet Security Research Group. The analysis confirms the seeds were generated using standard methods, not secret keys.
What made it possible
This incident highlights how pattern recognition can resolve long-standing cryptographic ambiguities. Teams usually examine historical software libraries when analyzing unexplained parameter origins. Checking for consistent bit patterns, such as zeroed high bits, can reveal the underlying generation method. Understanding the tooling available at the time of creation helps distinguish between malicious intent and standard procedural choices.
What to do and how to stay safe: Anthropic
- Review internal policies regarding the use of NIST-standard elliptic curves for digital signatures.
- Monitor vendor announcements for any changes to cryptographic recommendations based on new historical data.
- Ensure that security assessments include verification of parameter origins for critical infrastructure.
- Stay informed about developments in cryptographic standards from bodies like NIST and ANSI.
Step-by-step guide: DDoS Attack Mechanics: Answers to 10 Critical Questions
General security guidance from the RedTeam Tribune newsroom. It is not confirmed advice from the organisations named in this story.
Frequently asked questions
Did Claude break the encryption or expose secret keys?
No, the finding explains how public security parameters were chosen, rather than exposing secret keys or breaking encryption, according to Cyber Security News.
Which specific curves were analyzed?
The analysis covered NIST curves P-192, P-224, P-256, P-384, and P-521, plus five ANSI X9.62 example seeds.
What generator was used to create the seeds?
The seeds came from lrand48, a simple C random number generator, initialized with Unix timestamps between May 1997 and April 1998.
