Protecting against multi-step attacks of uncertain duration and timing forces defenders into an indefinite, always ongoing, resource-intensive response. To effectively allocate resources, a defender must be able to analyze multi-step attacks under assumption of constantly allocating resources against an uncertain stream of potentially undetected attacks. To achieve this goal, we present a novel methodology that applies a game-theoretic approach to the attack, attacker, and defender data derived from MITRE's ATT&CK Framework. Time to complete attack steps is drawn from a probability distribution determined by attacker and defender strategies and capabilities. This constraints attack success parameters and enables comparing different defender resource allocation strategies. By approximating attacker-defender games as Markov processes, we represent the attacker-defender interaction, estimate the attack success parameters, determine the effects of attacker and defender strategies, and maximize opportunities for defender strategy improvements against an uncertain stream of attacks. This novel representation and analysis of multi-step attacks enables defender policy optimization and resource allocation, which we illustrate using the data from MITRE's APT3 ATT&CK Evaluations.
翻译:为了有效分配资源,辩护人必须能够根据对可能无法察觉的攻击源源不绝地分配资源的假设,分析多步骤攻击。为了实现这一目标,我们提出了一个新方法,对攻击、攻击者和捍卫者采用游戏理论方法,从麻省理工学院的ATT&CK框架得出有关攻击、攻击者和袭击捍卫者的数据。完成攻击步骤的时间是根据攻击者和捍卫者的战略和能力决定的概率分布来决定的。这种限制攻击成功参数,使得能够比较不同的辩护人资源分配战略。我们以Markov进程的形式代表攻击者-抵抗者游戏,我们代表攻击者-抵抗者互动,估计攻击成功参数,确定攻击者和捍卫者战略的影响,并尽量扩大防御者战略改进机会,对付不确定的攻击潮。多步攻击的这种新颖的表述和分析使辩护人的政策优化和资源分配成为可能,我们用MITRE3 ATT&CK 评估的数据来说明。