Archive for 2015

Latest from Karsten Nohl: POS Security

Wednesday, December 30th, 2015

Karsten Nohl (PhD 2009) presented his work (with Fabian Bräunlein and Philipp Maier) on vulnerabilities in payment protocols (the ones studied are widely used in Germany but not in other countries) at the Chaos Communications Congress on December 27.

The work has been widely covered in the press recently. Here are a few sample articles:

- Watch infosec bods swipe PINs, magstripe data from card readers live on stage, The Register, 30 Dec 2015. (I trust the use of “bods” here is some kind of Britishism, not what it means in American.)

Now let’s look at Poseidon: a crook can buy a Poseidon payment terminal from the internet, and configure it to pretend to be a particular merchant’s systems. To do this, you need three bits of information, which are trivial to obtain…. Now you can perform arbitrary refunds, drawing money from the store’s funds. As there is no interruption to a merchant’s service, the seller will be none the wiser until he or she audits their finances. … German banks have shrugged off their research as merely “theoretical.”

- Payment system security is hilariously bad, BoingBoing (Cory Doctorow), 29 Dec 2015.

- Worries over German retail payments risks, Reuters, 23 December 2015.

A top cyber security researcher has warned German banks that their retail payment systems have security flaws that could allow fraudsters to steal payment card PIN codes, create fake cards or siphon funds from customer or merchant accounts.
Karsten Nohl, who is credited with revealing major security threats in mobile phones, automobiles, security cards and thumb-sized USB drives, told Reuters he has found critical weaknesses in software that runs retail point-of-sale terminals in Germany.

Dormant Malicious Code Discovered on Thousands of Websites

Tuesday, December 29th, 2015

Here’s the latest from Yuchen Zhou (PhD 2015, now at Palo Alto Networks): Dormant Malicious Code Discovered on Thousands of Websites, Yuchen Zhou and Wei Xu, Palo Alto Networks Blog, 14 November 2015.

During our continuous monitoring for a 24-hour period from November 11, 2015 to November 12, 2015, eight days after the initial discovery, the Chuxiong Archives website consistently presented malicious content injected by an attacker depending on the source IP and user agent. We believe that if a user were to visit the compromised website a second time following the initial exposure to the malicious code, the site would recognize the source IP and user-agent and simply remain dormant, not exhibiting any malicious behavior. Because of this anti-analysis/evasion technique, it may easily cause the belief that a website no longer poses a threat, when it remains infected.

At the time of this report, using our malicious web content scanning system, we have already discovered more than four thousands additional, similarly compromised websites globally exhibiting the same ability of being able to be dormant or active depending on source IP and user agent. Investigations regarding this campaign on a larger scale are ongoing and a second report detailing the similarly compromised websites will be published in the near future.

Evading Machine Learning Classifiers

Monday, December 21st, 2015

Today we’re releasing our paper on evading machine learning classifiers:

Weilin Xu, Yanjun Qi, and David Evans. Automatically Evading Classifiers: A Case Study on PDF Malware Classifiers Network and Distributed System Security Symposium (NDSS). San Diego, CA. 21-24 February 2016. [PDF, 15 pages]

The main idea behind the paper is to explore how an adaptive adversary can evade a machine learning-based malware classifier by using techniques from genetic programming to automatically explore the space of potential evasive variants.

In a case study using two PDF malware classifiers as targets, we find that it is possible to automatically find evasive variants (that is, variants that preserve the desired malicious behavior while being (mis)classified as benign) for all 500 seeds in our test dataset.

Weilin Xu will present the work at the Network and Distributed Systems Security Symposium in San Diego in February.

For more, see or the full paper (PDF).

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.’”

Trick or Treat?: Bitcoin for Non-Believers, Cryptocurrencies for Cypherpunks

Sunday, November 8th, 2015

I gave a talk at Johns Hopkins University for the DC-Area Crypto Day focused on cryptocurrencies: Trick or Treat?: Bitcoin for Non-Believers, Cryptocurrencies for Cypherpunks.

Video of the Entire Workshop

Great to include two recent alums, Alex Kuck and Nick Skelsey at the end of my talk. They talks about progress with Ombuds, a platform for free speech built on the blockchain.

Download slides: [PPTX (35 MB), PDF (4-up, 34MB)]

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?

USENIX PhD Forum Talk: How to Live in Paradise

Saturday, August 15th, 2015

I gave a talk at the USENIX Security Forum for new researchers on “How to Live in Paradise: A Guide for New and Disgruntled Professors” (reprising a similar talk I gave last year).

This website includes text expanding on the talk and a video of last year’s version.



Friday, June 5th, 2015

I went to a very interesting meeting at Darmstadt: CROSSING – Where Quantum Physics, Cryptography, System Security and Software Engineering meet. Lots more diversity than my typical computer security meeting, including a lively debate on quantum physics and superfluid vacuum theory between Nicolas Grisin (founder of ID Quantique and Ross Anderson. Interesting to learn that China is building a huge quantum key distribution network.

I gave a talk on Multi-Party Computation for the Masses:

CROSSING is a 12-year project funded by the German Science Foundation (with reviews every 4 years). Gives some context to US funding agencies that talk about long-range visionary projects with 5-year timelines.

SRG at Oakland 2015

Sunday, May 24th, 2015

Several SRGers were at IEEE Symposium on Security and Privacy (“Oakland” in San Jose).

Yuchen Zhou presented his work on Understanding and Monitoring Embedded Web Scripts. Yuchen graduated with his PhD the day before the conference, and will be joining Palo Alto Networks.

Samee Zahur is a co-author (along with Benjamin Kreuter, who is an “in-progress UVa PhD student” diverted by Google, and several researchers from Microsoft Research) on the paper, Geppetto: Versatile Verifiable Computation, which was presented by Bryan Parno.

Samee also presented a poster on Obliv-C.

Weilin Xu presented a poster on Automatically Evading Classifiers

It was also great to see SRG alums Yan Huang (who is not at Indiana University, and was a co-author on the paper about ObliVM), Jon McCune (who is now working on trusted computing at Google) and Adrienne Felt (who was the keynote speaker for the W2SP workshop, and gave a very interesting talk about user-facing security design and experiments in Google Chrome; Adrienne’s first paper was in W2SP 2008 when she was an undergraduate at UVa).

Graduates Lunch

Wednesday, May 6th, 2015

srg lunch

SRG Graduates Lunch, 6 May 2015