Anthropic says Claude proved security properties in 123 open-source libraries

Anthropic said its Claude models were able to produce formal proofs for security properties in compiled code across 123 open-source libraries, a result the company described as a step toward making formal software verification practical at much larger scale. In the research post published on Oct. 22, 2026, Anthropic said the work also surfaced bugs that had gone unnoticed for years. According to Anthropic, Claude proved that 239 entry points across those 123 libraries would not crash on any input below 64 MB under the project’s modeled conditions.

Source: Blockchain.News