SoK: Model Inversion Attack Landscape: Taxonomy, Challenges, and Future Roadmap

A crucial module of the widely applied machine learning (ML) model is the model training phase, which involves large-scale training data, often including sensitive private data. ML models trained on these sensitive data suffer from significant privacy concerns since ML models can intentionally or unintendedly leak information about training data. Adversaries can exploit this information to perform privacy attacks, including model extraction, membership inference, and model inversion. While a model extraction attack steals and replicates a trained model functionality, and membership inference infers the data sample's inclusiveness to the training set, a model inversion attack has the goal of inferring the training data sample's sensitive attribute value or reconstructing the training sample (i.e., image/audio/text). Distinct and inconsistent characteristics of model inversion attack make this attack even more challenging and consequential, opening up model inversion attack as a more prominent and increasingly expanding research paradigm. Thereby, to flourish research in this relatively underexplored model inversion domain, we conduct the first-ever systematic literature review of the model inversion attack landscape. We characterize model inversion attacks and provide a comprehensive taxonomy based on different dimensions. We illustrate foundational perspectives emphasizing methodologies and key principles of the existing attacks and defense techniques. Finally, we discuss challenges and open issues in the existing model inversion attacks, focusing on the roadmap for future research directions.