An AI security analyst is reviewing a system that uses a large language model (LLM) for customer support. The LLM is fine-tuned on internal documents and deployed via an API. The analyst wants to detect if an attacker is attempting to extract sensitive training data through crafted prompts. Which control is most effective for this detection?
Extraction attacks often involve systematic querying to reconstruct training data. By monitoring for repeated, structured, or high-volume queries that target specific information, security teams can detect and alert on potential extraction attempts. This behavioral analysis is effective because it focuses on the attacker's methodology rather than the content of individual prompts.
Why this answer
Detecting training data extraction requires identifying the behavioral signature of an attacker systematically probing the model. Monitoring query patterns for repetition, structure, and volume can reveal such attempts, whereas watermarking, similarity checks, and injection firewalls address different threats and do not reliably detect extraction.
Exam trap
The trap here is assuming that input filtering or output watermarking can detect extraction attacks, when detection actually relies on analyzing query behavior over time.