Iranian Society of Cryptology The ISC International Journal of Information Security 2008-2045 Articles in Press 2026 02 12 Mission-Centric Countermeasure Selection in Cybersecurity Situation Awareness Systems 240523 10.22042/isecure.2026.240523 EN Sajed Yousefi Mashhour Department of Management, Science and Technology, Amirkabir University of Technology, Tehran, Iran. Motahareh Dehghan Department of Industrial Engineering, Tarbiat Modares University, Tehran, Iran. 0000-0002-5316-8005 Babak Sadeghian Department of Computer Engineering, Amirkabir University of Technology, Tehran, Iran. Alireza Hashemi Golpayegani Department of Computer Engineering, Amirkabir University of Technology, Tehran, Iran. Journal Article Selecting optimal cybersecurity countermeasures requires integration with mission-critical objectives beyond technical risk minimization. This paper presents a mission-centric framework for countermeasure selection in cybersecurity situation awareness systems by extending the RiskMAP methodology with agent-based and discrete-event simulation. The framework employs a multi-criteria decision-making approach based on the Confidentiality, Integrity, and Availability (CIA) triad, weighing mission objectives and mapping vulnerabilities and threats using MITRE ATT&CK and D3FEND taxonomies. Candidate countermeasures are evaluated considering risk reduction, implementation cost, operational impact, and mission alignment. We demonstrate the approach through a case study on a critical infrastructure organization’s network modeled in AnyLogic. Results show improved alignment between security posture and organizational priorities while maintaining effective risk reduction, outperforming traditional methods. This framework enables quantitative visualization and optimization of security investments relative to mission continuity. All simulation models, data, and scripts are openly available to support reproducibility. https://www.isecure-journal.com/article_240523_fdd9635a99ae498880192e7e41bbf8b8.pdf