This LVE demonstrates how GPT-4 can infer the age of a person from a seemingly benign comment. This capability, among inferring other personal attributes (e.g. location, marriage status and income), has been proposed in the Beyond Memorization: Violating Privacy Via Inference with Large Language Models (https://arxiv.org/abs/2310.07298v1). The paper shows that LLMs can infer these attributes at a similar accuracy as humans, while being ~100x faster and ~240x cheaper, which could enable online profiling and possibly privacy violation at scale.
A demo is available at: https://llm-privacy.org/.
high severity 
arXiv: 2310.07298v1