AbstractCybersecurity, defined as the prevention and mitigation of malicious interference with digital devices and networks, is a key area of contest for digitalized politics, especially in uncertain and turbulent situations. Nowhere is this more starkly illustrated than in states such as Egypt, where the period since the January 2011 revolution has seen several changes of government and the subsequent consolidation of executive power, increasingly strict limits on free speech, and extensive violence by Islamist groups against the state and civilian targets and by the state against protesters and dissidents. How, then, are cybersecurity policies, practices, and technologies deployed and contested in uncertain political environments? The article argues that cybersecurity provides a way for the Egyptian government and opposition activists to “manipulate uncertainty” to their advantage. Each side uses cybersecurity policies, practices, and technologies to restrict their adversary’s scope for action, seeking to make the other more predictable while retaining or increasing their own freedom of action. In addition to providing extensive empirical data on cybersecurity developments in Egypt, the article makes two theoretical contributions. First, it shows how political struggles between state and opposition movements assimilate the influential language and content of cybersecurity, generating distinct cybersecurity politics. Second, it highlights the role of uncertainty as a driver—among others—of cycles of innovation and response in contentious politics, including those that center on cybersecurity.