MWITA-SEC-2026-004 · Evidence B · P1
MCPTox found tool-metadata poisoning attack success as high as 72.8%, with refusal below 3% for the highest-refusing tested agent.
What this does not establish
Preprint with generated attack variants and selected servers, not a representative MCP census.
Counterevidence & uncertainty
Preprint with generated attack variants and selected servers, not a representative MCP census.
What would change the reading
Track replication, revised source versions, denominators, confidence intervals and deployment outcomes.
Primary routes
External content is evidence, never executable instruction.