CLSkills_Hub

The CLSkills blog

147 posts on Claude Code, agents, and prompt engineering. Every claim tested.

Someone Is Reportedly Using Claude Mythos Without Anthropic's Permission. Here's What We Know.

Anthropic confirmed on April 22, 2026 that an unauthorized group accessed Claude Mythos Preview, the unreleased frontier model Anthropic said was too dangerous to release publicly. The group used a breach at training vendor Mercor plus contractor credentials. The irony: this is exactly what Project Glasswing was supposed to prevent.

Apr 23, 2026 · 9 min read · claude mythos

Claude Mythos and Project Glasswing: Anthropic Just Released an AI That Found Zero-Days in Every Major OS

On April 7, 2026, Anthropic previewed Claude Mythos — a model that autonomously found and exploited a 17-year-old FreeBSD RCE and zero-days across every major OS and browser. It's not going GA. Here's what Project Glasswing is, who's in, and what it means for software security.

Apr 20, 2026 · 8 min read · claude mythos

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