Confused deputy problem
The confused deputy problem is a classic security flaw where a program with legitimate authority to perform an action is tricked by a less-privileged caller into misusing that authority on the caller's behalf -- the "deputy" (the privileged program) is confused about whose request it's actually acting on. In MCP and other agent-tool systems, this shows up when a gateway or server simply passes through a token it received, rather than checking that the token was actually intended for it (the token's "audience"); a malicious client can then route a token meant for one service through to another, tricking the receiving service into granting access it never should have. The fix is validating token audience and scope at every hop, not forwarding credentials blindly between services.
By AdminKit team, Netbase JSC · Updated