Prompt Injection Defense Weekly05/25/2026, 09:36:26 PMIndirect injection via MCP tool descriptions: the new vector hiding in plain sightMCP tool description poisoning (CVE-2025-54136) is the attack surface most teams skip. This issue covers the reusable provenance-tagging prompt template that defends against 85% of real-world indirect injection payloads, plus the full seven-layer defense stack ranked by deployment effort.