Contrary to intuition, insecure computer network architectures are valuable assets in IT security. Indeed, such architectures (referred to as cyber-ranges) are commonly used to train red teams and test security solutions, in particular ones related to supervision security. Unfortunately, the design and deployment of these cyber-ranges is costly, as they require designing an attack scenario from scratch and then implementing it in an architecture on a case-by-case basis, through manual choices of machines/users, OS versions, available services and configuration choices. This article presents URSID, a framework for automatic deployment of cyber-ranges based on the formal description of attack scenarios. The scenario is described at the technical attack level according to the MITRE nomenclature, refined into several variations (instances) at the procedural level and then deployed in virtual multiple architectures. URSID thus automates costly manual tasks and allows to have several instances of the same scenario on architectures with different OS, software or account configurations. URSID has been successfully tested in an academic cyber attack and defense training exercise.