On the Risks of Distribution Inference
(Cross-post by Anshuman Suri)
Inference attacks seek to infer sensitive information about the training process of a revealed machine-learned model, most often about the training data.
Standard inference attacks (which we call “dataset inference attacks”) aim to learn something about a particular record that may have been in that training data. For example, in a membership inference attack (Reza Shokri et al., Membership Inference Attacks Against Machine Learning Models, IEEE S&P 2017), the adversary aims to infer whether or not a particular record was included in the training data.
Chinese Translation of MPC Book
A Chinese translation of our A Pragmatic Introduction to Secure Multi-Party Computation book (by David Evans, Vladimir Kolesnikov, and Mike Rosulek) is now available!
Thanks to Weiran Liu and Sengchao Ding for all the work they did on the translation.
To order from JD.com: https://item.jd.com/13302742.html
(The English version of the book is still available for free download, from https://securecomputation.org.)
ICLR DPML 2021: Inference Risks for Machine Learning
I gave an invited talk at the Distributed and Private Machine Learning (DPML) workshop at ICLR 2021 on Inference Risks for Machine Learning.
The talk mostly covers work by Bargav Jayaraman on evaluating privacy in machine learning and connecting attribute inference and imputation, and recent work by Anshuman Suri on property inference.
How to Hide a Backdoor
The Register has an article on our recent work on Stealthy Backdoors as Compression Artifacts: Thomas Claburn, How to hide a backdoor in AI software — Neural networks can be aimed to misbehave when squeezed, The Register, 5 May 2021.
Codaspy 2021 Keynote: When Models Learn Too Much
Here are the slides for my talk at the 11th ACM Conference on Data and Application Security and Privacy:
The talk includes Bargav Jayaraman’s work (with Katherine Knipmeyer, Lingxiao Wang, and Quanquan Gu) on evaluating privacy in machine learning, as well as more recent work by Anshuman Suri on property inference attacks, and Bargav on attribute inference and imputation:
- Merlin, Morgan, and the Importance of Thresholds and Priors
- Evaluating Differentially Private Machine Learning in Practice
“When models learn too much. “ Dr. David Evans @UdacityDave of University of Virginia gave a keynote talk on different inference risks for machine learning models this morning at #codaspy21 pic.twitter.com/KVgFoUA6sa
CrySP Talk: When Models Learn Too Much
I gave a talk on When Models Learn Too Much at the University of Waterloo (virtually) in the CrySP Speaker Series on Privacy (29 March 2021):
Abstract Statistical machine learning uses training data to produce models that capture patterns in that data. When models are trained on private data, such as medical records or personal emails, there is a risk that those models not only learn the hoped-for patterns, but will also learn and expose sensitive information about their training data. Several different types of inference attacks on machine learning models have been found, and methods have been proposed to mitigate the risks of exposing sensitive aspects of training data. Differential privacy provides formal guarantees bounding certain types of inference risk, but, at least with state-of-the-art methods, providing substantive differential privacy guarantees requires adding so much noise to the training process for complex models that the resulting models are useless. Experimental evidence, however, suggests that inference attacks have limited power, and in many cases a very small amount of privacy noise seems to be enough to defuse inference attacks. In this talk, I will give an overview of a variety of different inference risks for machine learning models, talk about strategies for evaluating model inference risks, and report on some experiments by our research group to better understand the power of inference attacks in more realistic settings, and explore some broader the connections between privacy, fairness, and adversarial robustness.
Improved Estimation of Concentration (ICLR 2021)
Our paper on Improved Estimation of Concentration Under ℓp-Norm Distance Metrics Using Half Spaces (Jack Prescott, Xiao Zhang, and David Evans) will be presented at ICLR 2021.
Abstract: Concentration of measure has been argued to be the fundamental cause of adversarial vulnerability. Mahloujifar et al. (2019) presented an empirical way to measure the concentration of a data distribution using samples, and employed it to find lower bounds on intrinsic robustness for several benchmark datasets. However, it remains unclear whether these lower bounds are tight enough to provide a useful approximation for the intrinsic robustness of a dataset. To gain a deeper understanding of the concentration of measure phenomenon, we first extend the Gaussian Isoperimetric Inequality to non-spherical Gaussian measures and arbitrary ℓp-norms (p ≥ 2). We leverage these theoretical insights to design a method that uses half-spaces to estimate the concentration of any empirical dataset under ℓp-norm distance metrics. Our proposed algorithm is more efficient than Mahloujifar et al. (2019)’s, and experiments on synthetic datasets and image benchmarks demonstrate that it is able to find much tighter intrinsic robustness bounds. These tighter estimates provide further evidence that rules out intrinsic dataset concentration as a possible explanation for the adversarial vulnerability of state-of-the-art classifiers.
Virginia Consumer Data Protection Act
Josephine Lamp presented on the new data privacy law that is pending in Virginia (it still needs a few steps including expected signing by governor, but likely to go into effect Jan 1, 2023): Slides (PDF)
This article provides a summary of the law: Virginia Passes Consumer Privacy Law; Other States May Follow, National Law Review, 17 February 2021.
The law itself is here: SB 1392: Consumer Data Protection Act
Algorithmic Accountability and the Law
Brink News (a publication of The Atlantic) published an essay I co-authored with Tom Nachbar (UVA Law School) on how the law views algorithmic accountability and the limits of what measures are permitted under the law to adjust algorithms to counter inequity:
Algorithms Are Running Foul of Anti-Discrimination Law
Tom Nachbar and David Evans
Brink, 7 December 2020
Computing systems that are found to discriminate on prohibited bases, such as race or sex, are no longer surprising. We’ve seen hiring systems that discriminate against women image systems that are prone to cropping out dark-colored faces and credit scoring systems that discriminate against minorities.
Microsoft Security Data Science Colloquium: Inference Privacy in Theory and Practice
Here are the slides for my talk at the Microsoft Security Data Science Colloquium:
When Models Learn Too Much: Inference Privacy in Theory and Practice [PDF]
The talk is mostly about Bargav Jayaraman’s work (with Katherine Knipmeyer, Lingxiao Wang, and Quanquan Gu) on evaluating privacy: