DRAFT: PLEASE DO NOT QUOTE OR CITE WITHOUT PERMISSION 1 Cyber attribution: technical and legal approaches and challenges Nicholas Tsagourias Michael D Farrell University of Sheffield Georgia Institute of Technology Sheffield, UK Atlanta, USA
[email protected] [email protected] Introduction Attribution describes the process of assigning a particular act to its source not necessarily in the sense of its physical perpetrator but more importantly in the sense of its mastermind. Attribution is important because it forms the basis of appropriate and effective technical, political and legal determinations and underpins technical, political and legal action and responsibility. In the cyber context, attribution has often been presented as a challenge because of the anonymity cyberspace affords, the possibility of spoofing, the multi-stage nature of cyber attacks, and the indiscriminate nature of cyber tools. To this, one should add the required human and technical resources, the lengthy time scales, and the associated investigatory demands. State to state attribution is treated with even more trepidation since the aforementioned problems are magnified whereas attribution or misattribution can engender serious consequences. Things, however, are changing. In the period 2007 to 2018, there have been more than twenty examples of high profile attribution claims of nation-state cyber attacks.1 These include attributions made by governments, civil society, and industry. One of the first public, high-profile instances of a large-scale cyberattack from a nation-state was the DDoS attack against the Estonian government, banks, and news agencies in 2007. The Prime Minister of Estonia, Andrus Ansip, attributed the attacks to Russia.2 This attribution received public criticism from Finnish security company F-secure,3 and was 1 The term cyber attack is used here to describe malicious cyber operations in general 2 Anderson, Nate.