Pipeline-parallel decentralised post-training, split across four nodes. Click any internal stage to place the compromised node — the task-vector injection indicator and attack metrics update to show 94% ASR collapsing alignment from 80% to 6%.
Controlling one intermediate pipeline stage is enough to inject a backdoor into a decentralized post-training run — 94% ASR, no data access required. The mechanism, why training loss stays clean, and what it means for networks fine-tuning LLMs across untrusted nodes.