Anthropic says Claude uncovers cryptographic weaknesses, advances AI-assisted security research

SAN FRANCISCO: Artificial intelligence firm Anthropic has said its Frontier Red Team has demonstrated that its latest AI models are beginning to make meaningful advances in cryptanalysis, with Claude uncovering previously unknown weaknesses in widely studied cryptographic algorithms and contributing to real-world security research.

In a research titled “Discovering cryptographic weaknesses with Claude,” Anthropic said the work marks an early step towards using frontier AI systems to strengthen cybersecurity by identifying flaws before they can be exploited by malicious actors. The company noted that while modern cryptographic systems remain highly secure, AI models are increasingly capable of assisting researchers in analyzing complex cryptographic constructions.

“Our models are beginning to contribute meaningfully to cryptographic research,” Anthropic said. The company said Claude was able to identify novel attacks against cryptographic schemes submitted to international standardisation efforts, with its findings subsequently reviewed and validated by human experts. According to Anthropic, the research demonstrates how AI can augment, rather than replace, specialist security researchers by accelerating the discovery of subtle vulnerabilities.

New Anthropic research: Discovering cryptographic weaknesses with Claude.

Claude Mythos Preview has helped our researchers find weaknesses in cryptographic algorithms—the mathematical methods that are used to keep data private.

Read more: https://t.co/TYKLjb3Q7V

— Anthropic (@AnthropicAI) July 28, 2026

“These results suggest that frontier AI systems are becoming increasingly capable of finding previously unknown cryptographic weaknesses,” the company said. Anthropic added that the work should not be interpreted as evidence that mainstream cryptographic standards are suddenly insecure, emphasizing that the affected schemes were primarily research proposals undergoing evaluation rather than widely deployed encryption systems. “The goal is to strengthen cryptography by finding weaknesses before attackers do,” Anthropic said.

The company also released CryptanalysisBench, a benchmark designed to evaluate AI models’ ability to perform cryptanalysis across a range of cryptographic primitives. Anthropic said it hopes the benchmark will help researchers track progress in AI-assisted cryptographic reasoning and identify emerging security risks as frontier models become more capable.

Anthropic said the findings underscore both the defensive potential and dual-use implications of advanced AI systems, reinforcing the need for continued evaluation of frontier models’ cyber capabilities alongside safeguards for their deployment. (ANI)