Anthropic published its report on the incident earlier this month. Jacob Klein, Anthropic’s head of threat intelligence, explained to me that the hackers took advantage of Claude’s “agentic” abilities—which enable the program to take an extended series of actions rather than focusing on one basic task. They were able to equip the bot with a number of external tools, such as password crackers, allowing Claude to analyze potential security vulnerabilities, write malicious code, harvest passwords, and exfiltrate data.