Anthropic logs eight months of Claude misuse

Anthropic says it identified and disrupted Claude misuse across seven harm areas over eight months, covering activity from December 2025 through August 2026 in its September threat-intelligence report. The report says none of those cases used Fable or Mythos-class models except one illicit-distillation case, and frames its examples as notable rather than typical. Builders should treat model access, compromised credentials, and autonomous workflows as a moving governance problem, budgeting monitoring and incident response before expanding tool permissions; AISI’s agent-evaluation evidence shows why scope and egress controls matter.