Agentic Backdoors via Pretraining Poisoning
Summary
This paper demonstrates that LLM pretraining on large, uncurated data can be poisoned to implant a remote code execution backdoor. The backdoor triggers attacker-chosen commands on the user’s machine, with attack success increasing with model size (about 92% ASR for a 4B model at 0.1% poisoning). The authors share their code on GitHub for reproducibility.