DualCF: Efficient Model Extraction Attack from Counterfactual Explanations. (arXiv:2205.06504v1 [cs.CR])

Cloud service providers have launched Machine-Learning-as-a-Service (MLaaS)
platforms to allow users to access large-scale cloudbased models via APIs. In
addition to prediction outputs, these APIs can also provide other information
in a more human-understandable way, such as counterfactual explanations (CF).
However, such extra information inevitably causes the cloud models to be more
vulnerable to extraction attacks which aim to steal the internal functionality
of models in the cloud. Due to the black-box nature of cloud models, however, a
vast number …

attack