titleSee it, Say it, Sorted: Mechanistic Diagnosis and Parameter-Space Mitigation of Emergent Misalignment in LLMs
authorsWeiqiao Que, Ruizhe Li, Chengyu Wang, Dakan Wang, Emine Yilmaz, Xiaofeng He
date2026-09-28
venuearXiv (preprint, not peer reviewed)
idarXiv:2609.34970
affiliationUniversity of Birmingham
upvotes4 (Hugging Face Daily Papers, 2026-11-01)
linksabs pdf hf code
abstractSafety-aligned LLMs can exhibit emergent misalignment (EM): narrow domain adaptation unexpectedly triggers catastrophic safety failures across unrelated domains. Prior static analyses leave training dynamics unmapped, while existing defenses rely on heuristics that degrade utility. We present a dynamic, second-order geometric study of EM. Tracking training trajectories reveals that directional Hessian curvature concentrates sharply on semantic pivot tokens. Grassmannian projections show that, in most settings, harmful-safe gap widens mainly because safe-gradient overlap declines. Leveraging these insights, we introduce a parameter-level Geometric Mitigation Framework that orthogonally projects empirical harmful gradient subspace out of parameter updates. On Qwen2.5-14B-IT, our defense suppresses free-generation EM by up to 80.0%; across the other three of four open-weight instruction-based model families (3B--20B), where single-layer behavioral EM is already near zero, teacher-forced evaluation shows same harmful subspace controls the conditional support of frozen EM responses. Crucially, these diagnostics unmask the illusion of behavioral safety: the same subspace remains measurable and steerable in models where behavioral EM is near zero. Code: https://github.com/WeiqiaoQUE/mechanistic-emergent-misalignment.

cite

@misc{que2026see,
  title={See it, Say it, Sorted: Mechanistic Diagnosis and Parameter-Space Mitigation of Emergent Misalignment in LLMs},
  author={Weiqiao Que and Ruizhe Li and Chengyu Wang and Dakan Wang and Emine Yilmaz and Xiaofeng He},
  year={2026},
  eprint={2609.34970},
  archivePrefix={arXiv},
  url={https://arxiv.org/abs/2609.34970}
}