This paper looks at the question of direct participation in cyber hostilities under the international law of armed conflict, or international humanitarian law (IHL) as it is also known. The paper examines the history and development of the concept of direct participation in hostilities by civilians, which serves as an exception to the principle of civilian or non-combatant immunity. In charting the development of the concept, this paper looks at landmark attempts to legally define the concept of direct participation, including the Israeli Targeted Killings Case, and the International Committee of the Red Cross (ICRC) study into direct participation. Using this legal background, this paper then analogises direct participation in the context of cyber hostilities, and critically examines the ways in which civilians may be deemed to be direct participating in cyber hostilities. The paper also posits some solutions to potentially problematic situations raised by civilian participation in cyber warfare.