US artificial intelligence firm Anthropic, the company behind the Claude AI model family, officially announced Claude Mythos Preview on 7 April, confirming it as a step-change model that poses what the company calls unprecedented cybersecurity risks.
The model’s existence first emerged in late March through a content management system misconfiguration that exposed around 3 000 draft blog posts, including one describing the new model.
According to Anthropic’s red-team documentation, the model – developed under the internal codename Capybara – can identify software vulnerabilities in minutes. The Adaptiva State of Patch Management 2025 report, by contrast, found that 77% of organisations globally need more than a week to deploy patches.
