T-MAP: Red-Teaming LLM Agents with Trajectory-aware Evolutionary Search

Hyomin Lee, Sangwoo Park, Yumin Choi, Sohyun An, Seanie Lee, Sung Ju Hwang


Abstract
While prior red-teaming efforts have focused on eliciting harmful text outputs from large language models (LLMs), such approaches fail to capture agent-specific vulnerabilities that emerge through multi-step tool execution, particularly in rapidly growing ecosystems such as the Model Context Protocol (MCP). To address this gap, we propose a trajectory-aware evolutionary search method, T-MAP, which leverages execution trajectories to guide the discovery of adversarial prompts. Our approach enables the automatic generation of attacks that not only bypass safety guardrails but also reliably realize harmful objectives through actual tool interactions. Empirical evaluations across diverse MCP environments demonstrate that T-MAP substantially outperforms baselines in attack realization rate (ARR) and remains effective against frontier models, including GPT-5.2, Gemini-3-Pro, Qwen3.5, and GLM-5, thereby revealing previously underexplored vulnerabilities in autonomous LLM agents. Code is available at https://github.com/pwnhyo/T-MAP.
Anthology ID:
2026.emnlp-main.68
Volume:
Proceedings of the 2026 Conference on Empirical Methods in Natural Language Processing
Month:
October
Year:
2026
Address:
Budapest, Hungary
Editors:
Hung-Yi Lee, Sunipa Dev, Jessy Li, Desmond Elliott
Venue:
EMNLP
SIG:
SIGDAT
Publisher:
Association for Computational Linguistics
Note:
Pages:
1558–1593
Language:
URL:
https://aclanthology.org/2026.emnlp-main.68/
DOI:
Bibkey:
Cite (ACL):
Hyomin Lee, Sangwoo Park, Yumin Choi, Sohyun An, Seanie Lee, and Sung Ju Hwang. 2026. T-MAP: Red-Teaming LLM Agents with Trajectory-aware Evolutionary Search. In Proceedings of the 2026 Conference on Empirical Methods in Natural Language Processing, pages 1558–1593, Budapest, Hungary. Association for Computational Linguistics.
Cite (Informal):
T-MAP: Red-Teaming LLM Agents with Trajectory-aware Evolutionary Search (Lee et al., EMNLP 2026)
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PDF:
https://aclanthology.org/2026.emnlp-main.68.pdf