ACDZero: Graph-Embedding-Based Tree Search for Mastering Automated Cyber Defense

Jan 1, 2026·
Yu Li
,
Sizhe Tang
Rongqian Chen
Rongqian Chen
,
Fei Xu Yu
,
Guangyu Jiang
,
Mahdi Imani
,
Nathaniel D Bastian
,
Tian Lan

TL;DR

ACDZero masters automated cyber defense by pairing Monte Carlo Tree Search with graph-neural-network embeddings of the network state — a planning-centric alternative to deep RL that achieves better defense reward, robustness, and sample efficiency.

Key contributions:

  • Frames automated cyber defense as a POMDP and solves it with MCTS guided by learned graph embeddings, balancing exploration and exploitation.
  • GNN-based, permutation-invariant reasoning over hosts and their relationships as attributed graphs.
  • Policy distillation with look-ahead planning, yielding improved defense reward and robustness over state-of-the-art RL baselines across CAGE Challenge 4 scenarios.

BibTeX

@article{li2026acdzero,
  title={ACDZero: Graph-Embedding-Based Tree Search for Mastering Automated Cyber Defense},
  author={Li, Yu and Tang, Sizhe and Chen, Rongqian and Yu, Fei Xu and Jiang, Guangyu and Imani, Mahdi and Bastian, Nathaniel D and Lan, Tian},
  journal={arXiv preprint arXiv:2601.02196},
  year={2026}
}