Archive for the 'Privacy' Category

Alumna-Turned-Internet Security Expert Listed Among Nation’s Top Young Innovators

Friday, September 22nd, 2017

Adrienne Porter Felt (SRG BSCS 2008) was selected as one of Technology Review’s 35 Innovators Under 35.

UVA Today has an article:Alumna-Turned-Internet Security Expert Listed Among Nation’s Top Young Innovators, UVA Today, 21 September 2017.

Felt started working in security when she was a second-year engineering student, responding to a request from computer science professor David Evans, who taught the “Program and Data Representation” course. Evans said Felt stood out amongst her peers because of her “well-thought-out answers and meticulous diagrams.”

“For the summer after her second year, she joined a project one of my Ph.D. students was working on to use the disk drive controller to detect malware based on the reads and writes it makes that are visible to the disk,” Evans said. “She did great work on that project, and by the end of the summer was envisioning her own research ideas.

“She came up with the idea of looking at privacy issues in Facebook applications, which, back in 2007, was just emerging, and no one else was yet looking into privacy issues like this.”

Taking Evans’ offer for a research project was a turning point in Felt’s life, showing her something she liked that she could do well.

“It turned out that I really loved it,” she said. “I like working in privacy and security because I enjoy helping people control their digital experiences. I think of it as, ‘I’m professionally paranoid, so that other people don’t need to be.’”

In her final semester as an undergraduate student at UVA, Felt taught a student-led class on web browsers.

“Her work at Google has dramatically changed the way web browsers convey security information to users, making the web safer for everyone,” Evans said. “Her team at Google has been studying deployment of HTTPS, the protocol that allows web clients to securely communicate with servers, and has had fantastic success in improving security of websites worldwide, as well as a carefully designed plan to use browser interfaces to further encourage adoption of secure web protocols.

Modest Proposals for Google

Friday, June 9th, 2017

Great to meet up with Wahooglers Adrienne Porter Felt, Ben Kreuter, Jonathan McCune, Samee Zahur (Google’s latest addition from my group), and (honorary UVAer interning at Google this summer) Riley Spahn at Google’s Research Summit on Security and Privacy this week in Mountain View.

As part of the meeting, the academic attendees were given a chance to give a 3-minute pitch to tell Google what we want them to do. The slides I used are below, but probably don’t make much sense by themselves.

The main modest proposal I tried to make is that Google should take it on as their responsibility to make sure nothing bad ever happens to anyone anywhere. They can start with nothing bad ever happening on the Internet, but with the Internet pretty much everywhere, should expand the scope to cover everywhere soon.

To start with an analogy from the days when Microsoft ruled computing. There was a time when Windows bluescreens were a frequent experience for most Windows users (and at the time, this pretty much mean all computer users). Microsoft analyzed the crashes and concluded that nearly all were because of bugs in device drivers, so it wasn’t their fault and was horribly unfair for them to be blamed for the crashes. Of course, to people losing their work because of a crash, it doesn’t really matter who’s code was to blame. By the end of the 90s, though, Microsoft took on the mission of reducing the problems with device drivers, and a lot of great work came out of this (e.g., the Static Driver Verifier), with dramatic improvements on the typical end user’s computing experience.

Today, Google rules a large chunk of computing. Lots of bad things happen on the Internet that are not Google’s fault. As the latest example in the news, the leaked NSA report of Russian attacks on election officials describes a phishing attack that exploits vulnerabilities in Microsoft Word. Its easy to put the blame on overworked election officials who didn’t pay enough attention to books on universal computation they read when they were children, or to put it on Microsoft for allowing Word to be exploited.

But, Google’s name is also all over this report – the emails when through gmail accounts, the attacks phished for Google credentials, and the attackers used plausibly-named gmail accounts. Even if Google isn’t too blame for the problems that enable such an attack, they are uniquely positioned to solve it, both because of their engineering capabilities and resources, but also because of the comprehensive view they have of what happens on the Internet and powerful ability to influence it.

Google is a big company, with lots of decentralized teams, some of which definitely seem to get this already. (I’d point to the work the Chrome Security Team has done, MOAR TLS, and RAPPOR as just a few of many examples of things that involve a mix of techincal and engineering depth and a broad mission to make computing better for everyone, not obviously connected to direct business interests.) But, there are also lots of places where Google doesn’t seem to be putting serious efforts into solving problems they could but viewing them as outside scope because its really someone else’s fault (my particular motivating example was PDF malware). As a company, Google is too capable, important, and ubiquitous to view problems as out-of-scope just because they are obviously undecidable or obviously really someone else’s fault.

[Also on Google +]

Aggregating Private Sparse Learning Models Using Multi-Party Computation

Friday, December 9th, 2016

Bargav Jayaraman presented on privacy-preserving sparse learning at the Private Multi‑Party Machine Learning workshop attached to NIPS 2016 in Barcelona.

A short paper summarizing the work is: Lu Tian, Bargav Jayaraman, Quanquan Gu, and David Evans. Aggregating Private Sparse Learning Models Using Multi-Party Computation [PDF, 6 pages].

At the workshop, Jack Doerner also presented a talk on An Introduction to Practical Multiparty Computation.

Secure Stable Matching at Scale

Tuesday, August 30th, 2016

Our paper on secure stable matching is now available [PDF, 12 pages]:

Jack Doerner, David Evans, abhi shelat. Secure Stable Matching at Scale. 23rd ACM Conference on Computer and Communications Security (CCS). Vienna, Austria. 24-28 October 2016.

See the site for the code and data. Jack Doerner will present the paper at CCS in October.


When a group of individuals and organizations wish to compute a stable matching — for example, when medical students are matched to medical residency programs — they often outsource the computation to a trusted arbiter to preserve the privacy of participants’ preference rankings. Secure multi-party computation presents an alternative that offers the possibility of private matching processes that do not rely on any common trusted third party. However, stable matching algorithms are computationally intensive and involve complex data-dependent memory access patterns, so they have previously been considered infeasible for execution in a secure multiparty context on non-trivial inputs.

We adapt the classic Gale-Shapley algorithm for use in such a context, and show experimentally that our modifications yield a lower asymptotic complexity and more than an order of magnitude in practical cost improvement over previous techniques. Our main insights are to design new oblivious data structures that exploit the properties of the matching algorithms. We then apply our secure computation techniques to the instability chaining algorithm of Roth and Peranson, currently in use by the National Resident Matching Program. The resulting algorithm is efficient enough to be useful at the scale required for matching medical residents nationwide, taking just over 17 hours to complete an execution simulating the 2016 NRMP match with more than 35,000 participants and 30,000 residency slots.

FTC Visit

Thursday, August 18th, 2016

Great to visit our former student Joseph Calandrino at the Federal Trade Commission in DC, where he is now a Research Director.

Denis Nekipelov and I gave a joint talk there about using secure multi-party computation techniques to enable data analyses across sensitive, divided data sets in the room where the FTC commissioners meet.

Denis Nekipelov, Joseph Calandrino, David Evans, Devesh Ravel

SRG at Oakland 2016

Wednesday, May 25th, 2016

At the IEEE Symposium on Security and Privacy in San Jose, CA, Samee Zahur presented on Square-Root ORAM and Anant, Jack, and Sam presented posters.

Anant Kharkar
Evading Web Malware Classifiers using Genetic Programming

Jack Doerner
Secure Gale-Shapley: Efficient Stable Matching for Multi-Party Computation

Samuel Havron
Secure Multi-Party Computation as a Tool for Privacy-Preserving Data Analysis

Apple and the FBI

Thursday, February 25th, 2016

I’m quoted in this article on the controversy over the FBI’s requests to Apple for assistance in unlocking an iPhone used by one of the San Bernardino terrorists: Unlocking Terrorist’s iPhone Won’t Risk Your Security, Discovery News, 24 February 2016.

“Backdoors are complicated and impossible technical challenges and would risk everyone’s privacy,” Evans said. “But what the FBI is asking for is different from what Apple says the FBI is asking for.”

For the most part, I think the article gets things right. It is very misleading to conflate what the FBI has asked for here with a cryptographic backdoor that would indeed dangerously risk everyone’s privacy and security. I covered some of the technical aspects of this in my introductory computing course last week.

Computer Science Grad Stands Watch for Users of Google’s Popular Browser

Tuesday, December 8th, 2015

Adrienne Porter Felt (BSCS 2008) returned to UVa last Friday as a Distinguished Alumni Speaker. UVa Today published this article:

Computer Science Grad Stands Watch for Users of Google’s Popular Browser
, UVa Today, 7 December 2015.

Adrienne Porter Felt’s job is to keep you secure on Chrome.

Felt, 29, who earned a computer science degree from the University of Virginia in 2008, leads the usable security team at Google working on the popular Internet browser.

Taking Evans’ offer for a research project was a turning point in Felt’s life, showing her something she liked that she could do well.

“It turned out that I really loved it,” she said. “I like working in privacy and security because I enjoy helping people control their digital experiences. I think of it as, ‘I’m professionally paranoid so that other people don’t need to be.’”

Karsten Nohl Interview

Monday, August 31st, 2015

Atlas Obscura has an article about Karsten Nohl (PhD 2009):
Exit Interview: I’m A Crypto-Specialist Working To Secure the Internet For A Billion People, Jeremy Berke, 28 July 2015.

One of the things we’re building is a PayPal competitor–with a modest target of having a few hundred million customers. Everything in India is always on a massive scale. If you could get rid of PayPal passwords, and instead just have a fingerprint–if you could pay for goods at a store with just your fingerprint, that would simplify people’s lives a lot. It would also have the secondary effect of saving some of the security problems, like phishing, that we currently encounter. And this government database is a huge enabler.

If we already have a mandate to collect everybody’s fingerprints, why not use it in the customer’s benefit? The privacy risk is always there. That’s the law and I can’t argue with that. But if the law is already creating this risk, why not create opportunity in the same step?

Understanding and Monitoring Embedded Web Scripts

Thursday, March 26th, 2015

Modern web applications make frequent use of third-party scripts, often in ways that allow scripts loaded from external servers to make unrestricted changes to the embedding page and access critical resources including private user information. Our paper describing tools to assist site administrators in understanding, monitoring, and restricting the behavior of third-party scripts embedded in their site, and what we’ve learned by using them, is now available: Yuchen Zhou and David Evans, Understanding and Monitoring Embedded Web Scripts, IEEE Symposium on Security and Privacy 2015.

Yuchen will present the paper at the Oakland conference (in San Jose) this May.

Project Site: