Analysis

When the Manual Lies: A Realistic Benchmark to Evaluate MCP Poisoning Attacks for LLM Agents

Page published

Publication date unknown · First observed: 19 Oct 2026

Coverage timeline

discovered arxiv.org primary 19 Oct 2026auth0.comobserved

Single-source analysis — one report is available.

Why it matters

Confused-deputy failures can turn an AI agent’s legitimate permissions into unauthorized actions, making requester-aware authorization and separation of untrusted content from authority important defensive boundaries.

Auth0’s analysis explains how confused-deputy failures arise when privileged software processes requests without checking the requester’s authority, and warns that AI agents expand this risk. Supporting MCP research demonstrates how malicious instructions in tool-description metadata can redirect an agent’s planning and execution.