The Model Context Protocol (MCP) helps connect LLMs to external tools, databases, and APIs. But giving AI agents hands and feet to take real-world actions introduces an entirely new attack surface.
We just published a MCP Security Fundamentals Course on the freeCodeCamp.org YouTube channel.
This course walks you through the mechanics of agent exploitation and how to defend against them.
Traditional application security assumes deterministic code and predictable human or machine interactions. AI agents, however, introduce non-deterministic decision-makers right into your application logic. When an agent acts on untrusted data, classic bugs like command injection, privilege escalation, and token leakage execute at machine speed.
Throughout the course, Dan frames these challenges around Simon Willison’s "Lethal Trifecta" framework, which is the dangerous convergence of three distinct capabilities:
- Private Data
The agent has read access to sensitive internal records, source code, credentials, or private databases. - Untrusted Content
The agent ingests text from outside sources, including web pages, emails, customer tickets, public issues, or third-party tool schemas. - External Communications
The agent possesses the capability to transmit data outward through webhooks, markdown rendering, emails, or API calls.
When an agent holds all three capabilities simultaneously, it becomes structurally vulnerable to prompt-driven exploitation. You will learn how to break this trifecta through architectural boundaries rather than relying on brittle prompt filters.
Watch the full course for free on the freeCodeCamp.org YouTube channel and start hardening your AI agent integrations today (2-hour watch).