Anthropic opens Claude Mythos 5.1 to wider security audience with 3-tier CVP

Anthropic had been running two separate efforts: Project Glasswing, which gave Claude Mythos to organizations protecting critical software, and the Cyber Verification Program, which gave vetted organizations versions of Claude Opus and Sonnet with relaxed cyber-related restrictions. The new move folds both into a single structure with three tiers — Defense Access, Red Team Access, and Specialized Access — defined by what each type of user is allowed to do.

The tiering is the notable part. Defense Access covers incident response, malware reverse engineering, and vulnerability analysis. Red Team Access adds approved penetration testing and red-team activity, but still blocks operations that could cause large-scale disruption, such as ransomware deployment or damage to physical systems. Specialized Access, the least restricted, is reserved for select organizations permitted to test systems including aviation operations, power grids, telecom networks, interbank transfer infrastructure, and government administrative networks.

Alongside Claude Mythos 5.1, the tiers also draw on Claude Opus 5.5 and Claude Sonnet 5.5. How much this actually widens access is likely to depend on how Anthropic reviews applicants, since the most sensitive capabilities remain gated behind approval rather than being opened outright.