Category Archives: Academic papers

The emotional cost of cybercrime

We know more and more about the financial cost of cybercrime, but there has been very little work on its emotional cost. David Modic and I decided to investigate. We wanted to empirically test whether there are emotional repercussions to becoming a victim of fraud (Yes, there are). We wanted to compare emotional and financial impact across different categories of fraud and establish a ranking list (And we did). An interesting, although not surprising, finding was that in every tested category the victim’s perception of emotional impact outweighed the reported financial loss.

A victim may think that they will still be able to recover their money, if not their pride. That really depends on what type of fraud they facilitated. If it is auction fraud, then their chances of recovery are comparatively higher than in bank fraud – we found that 26% of our sample would attempt to recover funds lost in a fraudulent auction and approximately half of them were reimbursed (look at this presentation). There is considerable evidence that banks are not very likely to believe someone claiming to be a victim of, say, identity theft and by extension bank fraud. Thus, when someone ends up out of pocket, they will likely also go through a process of secondary victimisation where they will be told they broke some small-print rule like having the same pin for two of their bank cards or not using the bank’s approved anti-virus software, and are thus not eligible for any refund and it is all their own fault, really.

You can find the article here or here. (It was published in IEEE Security & Privacy.)

This paper complements and extends our earlier work on the costs of cybercrime, where we show that the broader economic costs to society of cybercrime – such as loss of confidence in online shopping and banking – also greatly exceed the amounts that cybercriminals actually manage to steal.

Efficient multivariate statistical techniques for extracting secrets from electronic devices

That’s the title of my PhD thesis, supervised by Markus Kuhn, which has become available recently as CL tech report 878:

In this thesis I provide a detailed presentation of template attacks, which are considered the most powerful kind of side-channel attacks, and I present several methods for implementing and evaluating this attack efficiently in different scenarios.

These contributions may allow evaluation labs to perform their evaluations faster, show that we can determine almost perfectly an 8-bit target value even when this value is manipulated by a single LOAD instruction (may be the best published results of this kind), and show how to cope with differences across devices, among others.

Some of the datasets used in my experiments along with MATLAB scripts for reproducing my results are available here:


Emerging, fascinating, and disruptive views of quantum mechanics

I have just spent a long weekend at Emergent Quantum Mechanics (EmQM15). This workshop is organised every couple of years by Gerhard Groessing and is the go-to place if you’re interested in whether quantum mechanics dooms us to a universe (or multiverse) that can be causal or local but not both, or whether we might just make sense of it after all. It’s held in Austria – the home not just of the main experimentalists working to close loopholes in the Bell tests, such as Anton Zeilinger, but of many of the physicists still looking for an underlying classical model from which quantum phenomena might emerge. The relevance to the LBT audience is that the security proofs of quantum cryptography, and the prospects for quantum computing, turn on this obscure area of science.

The two themes emergent from this year’s workshop are both relevant to these questions; they are weak measurement and emergent global correlation.

Weak measurement goes back to the 1980s and the thesis of Lev Vaidman. The idea is that you can probe the trajectory of a quantum mechanical particle by making many measurements of a weakly coupled observable between preselection and postselection operations. This has profound theoretical implications, as it means that the Heisenberg uncertainty limit can be stretched in carefully chosen circumstances; Masanao Ozawa has come up with a more rigorous version of the Heisenberg bound, and in fact gave one of the keynote talks two years ago. Now all of a sudden there are dozens of papers on weak measurement, exploring all sorts of scientific puzzles. This leads naturally to the question of whether weak measurement is any good for breaking quantum cryptosystems. After some discussion with Lev I’m convinced the answer is almost certainly no; getting information about quantum states takes exponentially much work and lots of averaging, and works only in specific circumstances, so it’s easy for the designer to forestall. There is however a question around interdisciplinary proofs. Physicists have known about weak measurement since 1988 (even if few paid attention till a few years ago), yet no-one has rushed to tell the crypto community “Sorry, guys, when we said that nothing can break the Heisenberg bound, we kinda overlooked something.”

The second theme, emergent global correlation, may be of much more profound interest, to cryptographers and physicists alike.

Continue reading Emerging, fascinating, and disruptive views of quantum mechanics

87% of Android devices insecure because manufacturers fail to provide security updates

We are presenting a paper at SPSM next week that shows that, on average over the last four years, 87% of Android devices are vulnerable to attack by malicious apps. This is because manufacturers have not provided regular security updates. Some manufacturers are much better than others however, and our study shows that devices built by LG and Motorola, as well as those devices shipped under the Google Nexus brand are much better than most. Users, corporate buyers and regulators can find further details on manufacturer performance at

We used data collected by our Device Analyzer app, which is available from the Google Play Store. The app collects data from volunteers around the globe and we have used data from over 20,000 devices in our study. As always, we are keen to recruit more contributors! We combined Device Analyzer data with information we collected on critical vulnerabilities affecting Android. We used this to develop the FUM score which can be used to compare the security provided by different manufacturers. Each manufacturer is given a score out of 10 based on: f, the proportion of devices free from known critical vulnerabilities; u, the proportion of devices updated to the most recent version; and m, the mean number of vulnerabilities the manufacturer has not fixed on any device.

The problem with the lack of updates to Android devices is well known and recently Google and Samsung have committed to shipping security updates every month. Our hope is that by quantifying the problem we can help people when choosing a device and that this in turn will provide an incentive for other manufacturers and operators to deliver updates.

Google has done a good job at mitigating many of the risks, and we recommend users only install apps from Google’s Play Store since it performs additional safety checks on apps. Unfortunately Google can only do so much, and recent Android security problems have shown that this is not enough to protect users. Devices require updates from manufacturers, and the majority of devices aren’t getting them.

For further information, contact Daniel Thomas and Alastair Beresford via

CHERI: Architectural support for the scalable implementation of the principle of least privilege

[CHERI tablet photo]
FPGA-based CHERI prototype tablet — a 64-bit RISC processor that boots CheriBSD, a CHERI-enhanced version of the FreeBSD operating system.
Only slightly overdue, this post is about our recent IEEE Security and Privacy 2015 paper, CHERI: A Hybrid Capability-System Architecture for Scalable Software Compartmentalization. We’ve previously written about how our CHERI processor blends a conventional RISC ISA and processor pipeline design with a capability-system model to provide fine-grained memory protection within virtual address spaces (ISCA 2014, ASPLOS 2015). In our this new paper, we explore how CHERI’s capability-system features can be used to implement fine-grained and scalable application compartmentalisation: many (many) sandboxes within a single UNIX process — a far more efficient and programmer-friendly target for secure software than current architectures.

Continue reading CHERI: Architectural support for the scalable implementation of the principle of least privilege

Decepticon: interdisciplinary conference on deception research

I’m at Decepticon 2015 and will be liveblogging the talks in followups to this post. Up till now, research on deception has been spread around half a dozen different events, aimed at cognitive psychologists, forensic psychologists, law enforcement, cybercrime specialists and others. My colleague Sophie van der Zee decided to organise a single annual event to bring everyone together, and Decepticon is the the result. With over 160 registrants for the first edition of the event (and late registrants turned away) it certainly seems to have hit a sweet spot.

Award-winning case history of the health privacy scandal

Each year we divide our masters of public policy students into teams and get them to write case studies of public policy failures. The winning team this year wrote a case study of the fiasco. The UK government collected personal health information on tens of millions of people who had had hospital treatment in England and then sold it off to researchers, drug companies and even marketing firms, with only a token gesture of anonymisation. In practice patients were easy to identify. The resulting scandal stalled plans to centralise GP data as well, at least for a while.

Congratulations to Lizzie Presser, Maia Hruskova, Helen Rowbottom and Jesse Kancir, who tell the story of how mismanagement, conflicts and miscommunication led to a failure of patient privacy on an industrial scale, and discuss the lessons that might be learned. Their case study has just appeared today in Technology Science, a new open-access journal for people studying conflicts that arise between technology and society. LBT readers will recall several posts reporting the problem, but it’s great to have a proper, peer-reviewed case study that we can give to future generations of students. (Incidentally, the previous year’s winning case study was on a related topic, the failure of the NHS National Programme for IT.)

Crypto Wars 2.0

Today we unveil a major report on whether law enforcement and intelligence agencies should have exceptional access to cryptographic keys and to our computer and communications data generally. David Cameron has called for this, as have US law enforcement leaders such as FBI Director James Comey.

This policy repeats a mistake of the 1990s. The Clinton administration tried for years to seize control of civilian cryptography, first with the Clipper Chip, and then with various proposals for ‘key escrow’ or ‘trusted third party encryption’. Back then, a group of experts on cryptography and computer security got together to explain why this was a bad idea. We have now reconvened in response to the attempt by Cameron and Comey to resuscitate the old dead horse of the 1990s.

Our report, Keys Under Doormats: Mandating insecurity by requiring government access to all data and communications, is timed to set the stage for a Wednesday hearing of the Senate Judiciary Committee at which Mr Comey will present his proposals. The reply to Comey will come from Peter Swire, who was on the other side twenty years ago (he was a Clinton staffer) and has written a briefing on the first crypto war here. Peter was recently on President Obama’s NSA review group. He argues that the real way to fix the problems complained of is to fix the mutual legal assistance process – which is also my own view.

Our report is also highly relevant to the new ‘Snoopers’ Charter’ that Home Secretary Teresa May has promised to put before parliament this fall. Mrs May has made clear she wants access to everything.

However this is both wrong in principle, and unworkable in practice. Building back doors into all computer and communication systems is against most of the principles of security engineering, and it also against the principles of human rights. Our right to privacy, set out in section 8 of the European Convention on Human Rights, can only be overridden by mechanisms that meet three tests. First, they must be set out in law, with sufficient clarity for their effects to be foreseeable; second, they must be proportionate; third, they must be necessary in a democratic society. As our report makes clear, universal exceptional access will fail all these tests by a mile.

For more, see the New York Times.

Passwords 2015 call for papers

The  9th International Conference on Passwords will be held at Cambridge, UK on 7-9 December 2015.

Launched in 2010 by Per Thorsheim,  Passwordscon is a lively and entertaining conference series dedicated solely to passwords. Passwordscon’s unique mix of refereed papers and hacker talks encourages a kind of cross-fertilization that I’m sure you’ll find both entertaining and fruitful.

Paper submissions are due by 7 September 2015. Selected papers will be included in the event proceedings, published by Springer in the Lecture Notes in Computer Science (LNCS) series.

We hope to see lots of you there!

Graeme Jenkinson, Local arrangements chair