Fact-checking Donald Trump’s tweet firing Christopher Krebs

I was a source for thie “Pants on Fire!” fact check by PolitiFact on Donald Trump’s tweet that fired Christopher Krebs claiming that “The recent statement by Chris Krebs on the security of the 2020 Election was highly inaccurate, in that there were massive improprieties and fraud - including dead people voting, Poll Watchers not allowed into polling locations, “glitches” in the voting machines which changed…” PolitiFact: Fact-checking Donald Trump’s tweet firing Christopher Krebs, 18 November 2020

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Voting Security

I was interviewed for a local news story by Daniel Grimes on election security: UVA cybersecurity expert: Virginia is one of the safer states to cast a ballot, NBC 29 News, 21 October 2020.

Merlin, Morgan, and the Importance of Thresholds and Priors

Post by Katherine Knipmeyer Machine learning poses a substantial risk that adversaries will be able to discover information that the model does not intend to reveal. One set of methods by which consumers can learn this sensitive information, known broadly as membership inference attacks, predicts whether or not a query record belongs to the training set. A basic membership inference attack involves an attacker with a given record and black-box access to a model who tries to determine whether said record was a member of the model’s training set.

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Adversarially Robust Representations

Post by Sicheng Zhu With the rapid development of deep learning and the explosive growth of unlabeled data, representation learning is becoming increasingly important. It has made impressive applications such as pre-trained language models (e.g., BERT and GPT-3). Popular as it is, representation learning raises concerns about the robustness of learned representations under adversarial settings. For example, how can we compare the robustness to different representations, and how can we build representations that enable robust downstream classifiers?

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Intrinsic Robustness using Conditional GANs

The video of Xiao’s presentation for AISTATS 2020 is now available: Understanding the Intrinsic Robustness of Image Distributions using Conditional Generative Models Starting with Gilmer et al. (2018), several works have demonstrated the inevitability of adversarial examples based on different assumptions about the underlying input probability space. It remains unclear, however, whether these results apply to natural image distributions. In this work, we assume the underlying data distribution is captured by some conditional generative model, and prove intrinsic robustness bounds for a general class of classifiers, which solves an open problem in Fawzi et al.

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Hybrid Batch Attacks at USENIX Security 2020

Here’s the video for Fnu Suya’s presentation on Hybrid Batch Attacks at USENIX Security 2020:

Download Video [mp4]

Blog Post
Paper: [PDF] [arXiv]

Pointwise Paraphrase Appraisal is Potentially Problematic

Hannah Chen presented her paper on Pointwise Paraphrase Appraisal is Potentially Problematic at the ACL 2020 Student Research Workshop: The prevailing approach for training and evaluating paraphrase identification models is constructed as a binary classification problem: the model is given a pair of sentences, and is judged by how accurately it classifies pairs as either paraphrases or non-paraphrases. This pointwise-based evaluation method does not match well the objective of most real world applications, so the goal of our work is to understand how models which perform well under pointwise evaluation may fail in practice and find better methods for evaluating paraphrase identification models.

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De-Naming the Blog

This blog was started in January 2008, a bit over eight years after I started as a professor at UVA and initiated the research group. It was named after Thomas Jefferson’s cipher wheel, which has long been (and remains) one of my favorite ways to introduce cryptography. Figuring out how to honor our history, including Jefferson’s founding of the University, and appreciate his ideals and enormous contributions, while confronting the reality of Jefferson as a slave owner and abuser, will be a challenge and responsibility for people above my administrative rank.

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Oakland Test-of-Time Awards

I chaired the committee to select Test-of-Time Awards for the IEEE Symposium on Security and Privacy symposia from 1995-2006, which were presented at the Opening Section of the 41st IEEE Symposium on Security and Privacy.

NeurIPS 2019

Here's a video of Xiao Zhang's presentation at NeurIPS 2019:
https://slideslive.com/38921718/track-2-session-1 (starting at 26:50)

See this post for info on the paper.

Here are a few pictures from NeurIPS 2019 (by Sicheng Zhu and Mohammad Mahmoody):

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