UC-014: Parameter Injection Attempt

Layer: B — Dispatch Enforcement Threat: Parameter Injection (OWASP MCP)

Scenario

A tool call includes extra/hidden fields not in the pinned schema, or arguments that embed command injection payloads.

Expected Behavior

• Extra/unknown args in tool call → DENY
• JCS canonicalization normalizes before evaluation
• Schema validation rejects non-conforming fields

Pass Criteria

• Verdict: DENY
• Reason code: DENY (schema violation)
• Receipt: signed deny receipt with ArgsHash
• No execution occurs