OpenAI, Anthropic, and 100+ companies warn of a closing window on cyber defense

OpenAI, Anthropic, Microsoft, Google, AWS, and 100+ other companies signed an open letter warning that AI-enabled cyberattacks will become “far more widespread and sophisticated” in the coming months, and that defenders have a limited window to prepare. The letter calls on frontier AI labs to give vetted defenders early model access, funding, and training, and singles out hospitals, water utilities, and legacy infrastructure as especially exposed. It sets no deadlines or spending pledges, and follows OpenAI’s own admission it could have reacted sooner to prevent the Hugging Face breach.

This is a coordinated industry signal, not a compliance mandate - enterprises running legacy or under-patched systems should read it as an early warning worth acting on now.