Prompt Injection Success Rate Exceeds 85% Against SOTA Defenses When Adaptive Strategies Are Used

ScienceDirect·medium signal

A meta-analysis of 78 recent studies (2021-2026) published in ScienceDirect consolidates evidence that attack success rates against state-of-the-art prompt injection defenses exceed 85% when adaptive attack strategies are employed. The study catalogs 31 distinct attack techniques including protocol-level attacks specific to MCP ecosystems. However, a HITL defense layer improves protection to 91.5%. An open-source agent firewall with an 11-layer pipeline for DLP and MCP tool poisoning detection shows the most promise for production defense.