Big AI broke the internet. Now it wants everyone else to fix it.

A joint letter published on OpenAI’s website warns that AI-enabled cyberattacks are becoming more widespread and sophisticated, urging corporations, cybersecurity firms and governments to reduce damage before it escalates. The signatories include OpenAI, Anthropic, Google, Microsoft and Perplexity, among others. The letter argues there is a limited window to strengthen cyber defenses, citing growing AI capability and the risk to services communities depend on, from hospitals to water treatment and internet infrastructure. It also raises accountability concerns, noting the companies that built the systems are the ones now posing the hazard, while urging coordinated defensive action.