AION
Research paperReinforcement Learning · Training & Scaling · Large Language Models1 source · Oct 6, 2026

AdvSim2Real : Training Web Agents Against Adaptive Prompt Injection in a Web World Model

We introduce AdvSim2Real, which co-evolves a task curriculum, an injection adversary, and the agent inside a frozen web world model.

Key points

  • Web agents complete user requests by reading and acting on pages that third parties write, so an instruction planted on a page can redirect the agent away from the user's goal.
  • Current defenses fine-tune the agent on injections fixed before training, and attackers that adapt to the trained model bypass them.
  • Adversarial training lets the attacker adapt but keeps the tasks fixed, so a task stops teaching once the agent solves it.
  • Training in the simulator makes a 4B agent both more capable and more robust: its completion rises with and without attacks, holds against a frontier-model adversary it never trained against, and its capability gain carries over to a real browser.

Sources (1)

  • [1]AdvSim2Real : Training Web Agents Against Adaptive Prompt Injection in a Web World Model
    arXiv (AI, ML, NLP, CV, robotics, multi-agent) · Oct 6, 05:56 PM
    We introduce AdvSim2Real, which co-evolves a task curriculum, an injection adversary, and the agent inside a frozen web world model.
    Web agents complete user requests by reading and acting on pages that third parties write, so an instruction planted on a page can redirect the agent away from the user's goal.

Extractive summary: sentences quoted from the sources.