Anthropic's Mythos model created fake online identities as it looked to pressure humans into approving malicious code updates to an open source project, marking yet another cyber incident carried out by a frontier AI system. The incident happened during a cyber evaluation where the U.K.-based AI Security Institute (AISI), a research body, had removed safeguards, disabled some safety filters, and deliberately given the models Internet access. It comes after a series of cyber breaches carried out by models developed by Anthropic and OpenAI in recent weeks. watch nowDuring the routine cyber evaluation, the AISI identified AI agents powered by Anthropic and OpenAI models had engaged "in sustained, potentially harmful activity directed at real people and organisations." It's the latest in a string of cyber incidents that have thrown up big questions around the safety of frontier AI systems.