Title: Discussion 9 — Fixing the "Union of Everyone's Permissions" Anti-Pattern
Course: AIINFRA 302: AI Security, Guardrails & Governance > Section: Week 09 — Data Privacy, Secrets Management, and Access Control

💬 Discussion 9 — Fixing the "Union of Everyone's Permissions" Anti-Pattern (20 pts)

If "the model inherits the union of everyone's permissions" is the anti-pattern we need to eliminate, what retrieval-time control would you add to a RAG system that currently indexes documents without any per-user access checks? In your initial post (150+ words), pick a concrete scenario (e.g., an internal HR RAG bot, a customer support knowledge base, a company-wide document search assistant) and describe:

- What retrieval-time control(s) you would add — be specific about whether it's document-level RBAC, attribute-based access control (ABAC), metadata filtering at query time, or something else.
- Where in the pipeline the check should happen (at ingestion/indexing time, at retrieval time, or both) and why that matters.
- One tradeoff of your approach (e.g., performance cost of per-query filtering, complexity of maintaining permission metadata as documents change owners).

Then respond to at least two classmates — push on a gap in their proposed control (What happens when a document's permissions change after it's indexed? What if a user's role changes mid-session?) or share a different approach you've seen or read about.