Can LLMs Keep a Secret? Testing Privacy Implications of Language Models via Contextual Integrity Theory

Niloofar Mireshghallah, Hyunwoo Kim, Xuhui Zhou, Yulia Tsvetkov, Maarten Sap +2 more
2/12/2026

No official code found. Best implementation: skywalker023/confaide (57 stars, MIT, last commit 2023-12-20).

Abstract

The interactive use of large language models (LLMs) in AI assistants (at work, home, etc.) introduces a new set of inference-time privacy risks: LLMs are fed different types of information from multiple sources in their inputs and are expected to reason about what to share in their outputs, for what purpose and with whom, within a given context. In this work, we draw attention to the highly critical yet overlooked notion of contextual privacy by proposing ConfAIde, a benchmark designed to identify critical weaknesses in the privacy reasoning capabilities of instruction-tuned LLMs. Our experiments show that even the most capable models such as GPT-4 and ChatGPT reveal private information in contexts that humans would not, 39% and 57% of the time, respectively. This leakage persists even when we employ privacy-inducing prompts or chain-of-thought reasoning. Our work underscores the immediate need to explore novel inference-time privacy-preserving approaches, based on reasoning and theory of mind.

View on arXivView PDF

Code Implementations(1)

MIT

🤫 Code and benchmark for our ICLR 2024 spotlight paper: "Can LLMs Keep a Secret? Testing Privacy Implications of Language Models via Contextual Integrity Theory"

573PythonOct 24, 20232 years agoMIT

Similar Papers

Cite this paper

@article{mireshghallah2026llms,
  title  = {Can LLMs Keep a Secret? Testing Privacy Implications of Language Models via Contextual Integrity Theory},
  author = {Niloofar Mireshghallah and Hyunwoo Kim and Xuhui Zhou and Yulia Tsvetkov and Maarten Sap and Reza Shokri and Yejin Choi},
  year   = {2026},
  eprint = {2310.17884},
  archivePrefix = {arXiv},
  url    = {https://arxiv.org/abs/2310.17884},
  journal = {ICLR 2023 2023}
}

Add a badge to your README

Shows whether official code is linked for this paper.

Code of Paper badge
[![Code of Paper](https://codeofpaper.com/badge/2310.17884.svg)](https://codeofpaper.com/paper/2310.17884)

Discussion