Why it matters

Agents load tools, MCP servers, plugins and prompt templates at run time, so a malicious or compromised component immediately gains the agent’s access.

How to prevent it

  • Allowlist and pin the tools, servers and plugins an agent may load, and verify their integrity.
  • Treat tool descriptions and metadata as untrusted input, and review changes to them.
  • Run third-party components with least privilege, isolated from secrets.

Guides on this site

Practice

References

  1. OWASP Top 10 for Agentic Applications for 2026 (OWASP GenAI Security Project, Agentic Security Initiative)

List data from the publisher. A guide is listed as the main subject when the weakness or risk is what the guide is about, and as covering it when a dedicated section or worked example addresses it.