Claude Mythos Preview
Anthropic's gated frontier research preview with step-change autonomous cybersecurity capabilities (Project Glasswing access only)
Claude Mythos Preview
Anthropic • April 2026
Training Data
Not disclosed
Claude Mythos Preview
April 2026
Parameters
Not disclosed
Training Method
Not disclosed
Context Window
Not disclosed
Knowledge Cutoff
Not disclosed
Key Features
Gated Research Preview • Autonomous Vulnerability Discovery • Project Glasswing Only • Not Publicly Released
Capabilities
Security: Outstanding (autonomous exploit dev)
Reasoning: Frontier
Coding: Outstanding
Autonomy: Outstanding
What's New in This Version
Qualitative leap over Opus 4.6 in autonomous exploit development — discovered & exploited CVE-2026-4747 (17-year-old FreeBSD NFS RCE)
Anthropic's gated frontier research preview with step-change autonomous cybersecurity capabilities (Project Glasswing access only)
What's New in This Version
Qualitative leap over Opus 4.6 in autonomous exploit development — discovered & exploited CVE-2026-4747 (17-year-old FreeBSD NFS RCE)
Technical Specifications
Key Features
Capabilities
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