Dr Steven J. Murdoch
I am a Royal Society University Research Fellow in the Information Security Research Group of the Department of Computer Science at University College London. I am also a bye-fellow of Christ’s College, Security Architect at the OneSpan Innovation Center, Cambridge, a member of the Tor Project, and a Fellow of the IET and BCS.
I am always interested in recruiting talented researchers to join my team at UCL, both as PhD students and for post-doctoral positions. Interested candidates should email me their curriculum vitae and a short research proposal.
For more details see my full list of publications or my Google Scholar page. I also write articles on information security for the UCL Information Security Group blog – Bentham’s Gaze, and my occasional non-security articles are published on my personal blog.
- Scanning the Internet for Liveness
Shehar Bano, Philipp Richter, Mobin Javed, Srikanth Sundaresan, Zakir Durumeric, Steven J. Murdoch, Richard Mortier, Vern Paxson
Internet-wide scanning depends on a notion of liveness: does a target IP address respond to a probe packet? However, the interpretation of such responses, or lack of them, is nuanced and depends on multiple factors, including: how we probed, how different protocols in the network stack interact, the presence of filtering policies near the target, and temporal churn in IP responsiveness. Although often neglected, these factors can significantly affect the results of active measurement studies. We develop a taxonomy of liveness which we employ to develop a method to perform concurrent IPv4 scans using ICMP, five TCP-based, and two UDP-based protocols, comprehensively capturing all responses to our probes, including negative and cross-layer responses. Leveraging our methodology, we present a systematic analysis of liveness and how it manifests in active scanning campaigns, yielding practical insights and methodological improvements for the design and the execution of active Internet measurement studies.
ACM SIGCOMM Computer Communication Review, Volume 48, Issue 2, Pages 2-9, ACM, April 2018. [ paper | DOI 10.1145/3213232.3213234 | code | data ]
- Incentives in Security Protocols
Alexander Hicks, Sarah Azouvi, Steven J. Murdoch
Real world protocols often involve human choices that depend on incentives, including when they fail and require fail-safe or fail-deadly mechanisms. We look at three example systems (the EMV protocol, consensus in cryptocurrencies, and Tor) in this context, paying particular attention to the role that incentives play in fail-safe and fail-deadly situations. We argue that incentives should explicitly be taken into account in the design of security protocols, and discuss general challenges in doing so.
International Workshop on Security Protocols, Cambridge, UK, 19–21 March 2018. [ paper | slides ]
- International comparison of bank fraud reimbursement: customer perceptions and contractual terms
Ingolf Becker, Alice Hutchings, Ruba Abu-Salma, Ross Anderson, Nicholas Bohm, Steven J. Murdoch, M. Angela Sasse, Gianluca Stringhini
The study presented in this article investigated to what extent bank customers understand the terms and conditions (T&Cs) they have signed up to. If many customers are not able to understand T&Cs and the behaviours they are expected to comply with, they risk not being compensated when their accounts are breached. An expert analysis of 30 bank contracts across 25 countries found that most contract terms were too vague for customers to infer required behaviour. In some cases the rules vary for different products, meaning the advice can be contradictory at worst. While many banks allow customers to write Personal identification numbers (PINs) down (as long as they are disguised and not kept with the card), 20% of banks categorically forbid writing PINs down, and a handful stipulate that the customer have a unique PIN for each account. We tested our findings in a survey with 151 participants in Germany, the USA and UK. They mostly agree: only 35% fully understand the T&Cs, and 28% find important sections are unclear. There are strong regional variations: Germans found their T&Cs particularly hard to understand, and USA bank customers assumed some of their behaviours contravened the T&Cs, but were reassured when they actually read them.
Journal of Cybersecurity, Volume 3, Issue 2, Pages 109–125, Oxford University Press, 01 June 2017. [ paper | DOI 10.1093/cybsec/tyx011 | data ]
For more detail see my full list of talks
- Payment Security: Attacks & Defences
Steven J. Murdoch
This lecture provides an introduction to payment card and online banking security mechanisms and the fraud techniques which are designed to break or bypass these measures. An overview of the EMV protocol is given, along with an illustration of how skimming attacks and the no-PIN attack exploit protocol weaknesses. The man-in-the-browser attack is outlined, and how transaction authentication is intended to defend against this.
Guest lecture as part of COMPGA03 - Introduction to Cryptography, University College London, 13 December 2016. [ slides ]
- Decentralising Data Collection and Anonymisation
Steven J. Murdoch
A frequent approach for anonymising datasets is for individuals to submit sensitive data records to a central authority. The central authority then is responsible for safely storing and sharing the data, for example by aggregating or perturbing records. However, this approach introduces the risk that the central authority may be compromised, whether this from an externally originated hacking attempt or as a result of an insider attack. As a result, central authorities responsible for handling sensitive data records must be well protected, often at great expense, and even then the risk of compromise will not be eliminated. In this talk I will discuss an alternative anonymisation approach, where sensitive data records have identifiable information removed before being submitted to the central authority. In order for this approach to work, not only must this first-stage anonymisation prevent the data from disclosing the identity of the submitter, but also the data records must be submitted in such a way as to prevent the central authority from being able to establish the identity of the submitter from submission metadata. I will show how advances in network metadata anonymisation can be applied to facilitate this approach, including techniques to preserve validity of data despite not knowing the identity of contributors.
New Developments in Data Privacy, Isaac Newton Institute, 09 December 2016. [ slides | video ]
- Anonymity & Censorship-Free Communication
Steven J. Murdoch
This talk discusses the history of anonymous communication systems, their applications (including censorship resistance), how they are designed, and what cryptographic mechanisms they use. Techniques to measure and quantify the security levels provided by anonymous communication systems are also covered. Finally, challenges faced by such systems are discussed, along with future directions for research.
Invited talk at IFIP Summer School 2016, Karlstad, Sweden, 21–26 August 2016. [ slides | slides (PDF) ]
Alexander Hicks (PhD student, 2017–): privacy preserving continuous authentication.
Andreas Gutmann (PhD student, 2016–): privacy-preserving transaction authentication for mobile devices.
Shehar Bano (Research Assistant & PhD student, 2013–2016): measurement of censorship and censorship resistance systems.
Kumar Sharad (PhD student, 2012–2016): security in social networks – anonymisation and fraud prevention.
14th Privacy Enhancing Technologies Symposium, 16–18 July, 2014, Amsterdam, Netherlands.
15th Privacy Enhancing Technologies Symposium, 30 June–2 July 2015, Philadelphia, PA, USA.
Financial Cryptography and Data Security 2011, 15th International Conference, 28 February–4 March 2011, St. Lucia.
Programme committee membership
- IFIP Summer School 2016, 2017, 2018
- Financial Cryptography and Data Security (FC): 2010, 2016, 2018
- Privacy Enhancing Technologies Symposium (PETS): 2007, 2008, 2009, 2011, 2017, 2018
- Network and Distributed System Security Symposium (NDSS): 2017
- ACM Conference on Computer and Communications Security (CCS): 2007, 2008, 2010, 2011, 2016
- Annual Privacy Forum 2014
- Free and Open Communications on the Internet (FOCI) 2013
- USENIX Security 2012
- European Symposium on Research in Computer Security (ESORICS) 2011
- Workshop on Foundations of Security and Privacy (FCS-PrivMod): 2010
- Workshop on Privacy in the Electronic Society (WPES): 2006, 2007, 2009
- FIDIS/IFIP Internet Security & Privacy Summer School: 2008
- ACM Symposium on Applied Computing (Computer Security track): 2007
Includes Proceedings on Privacy Enhancing Technologies (2017, 2018), ACM Transactions on Internet Technology (TOIT) (2017), International Journal of Computer Security (2016), IEEE Transactions on Dependable and Secure Computing (2009), ACM Transactions on Information and System Security (2008), IEEE Transactions on Software Engineering (2008), IEEE/ACM Transactions on Networking (2007), IEEE Security & Privacy (2007), The Triple Helix (2008), Identity in the Information Society (2008).
s.murdoch at ucl.ac.uk
post:Dr Steven J. Murdoch
Computer Science Department
University College London