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arXiv · 2601.15824

Introducing the Generative Application Firewall (GAF)

Joan Vendrell Farreny·Martí Jordà Roca·Miquel Cornudella Gaya·Rodrigo Fernández Baón·Víctor García Martínez·Eduard Camacho Sucarrats·Alessandro Pignati
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Abstract

This paper introduces the Generative Application Firewall (GAF), a new architectural layer for securing LLM applications. Existing defenses -- prompt filters, guardrails, and data-masking -- remain fragmented; GAF unifies them into a single enforcement point, much like a WAF coordinates defenses for web traffic, while also covering autonomous agents and their tool interactions.

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Joan Vendrell Farreny, Martí Jordà Roca, Miquel Cornudella Gaya, Rodrigo Fernández Baón, Víctor García Martínez, Eduard Camacho Sucarrats, Alessandro Pignati. 2026-01-22. Introducing the Generative Application Firewall (GAF). https://arxiv.org/abs/2601.15824

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