From Automation to Infection (Part III): Naming, Measuring, and Detecting Malicious AI Agent Skills

In Part I and Part II of this series, we looked at an initial sample of 3,016 AI agent skills and showed how they were becoming a new supply-chain delivery channel. The flow of skills reaching VirusTotal keeps growing, so for this follow-up we expanded the study more than tenfold, to 35,878 skills from a snapshot of VirusTotal submissions, to get a more representative picture. Two findings stand out.