Abstract Multi-step attacks have been widely adopted by attackers, resulting in privacy leakage. Although many cost-sensitive approaches have been proposed to respond to the multi-step attacks, most studies have lack global optimization and ignored the fact that attackers may take multiple paths to launch multi-step attacks, which may lead to an over-response or an under-response. To address this problem, we formulate a response to multi-path attacks as an optimization problem and prove it is NP-hard. To obtain a feasible solution to the problem, we first identify suspicious attack paths and evaluate several metrics (i.e., security benefit, deployment cost, and negative impact on the quality of services) of the countermeasures. Specifically, by considering the compositions and cover degrees of atomic attacks, we define Attacks Surface Coverage to accurately evaluate the security benefit of countermeasures. Then, we propose an improved greedy algorithm to select reasonable countermeasures. Experimental results demonstrate the effectiveness and feasibility of our approach.

中文翻译：

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多路径攻击的动态对策选择

摘要 多步攻击被攻击者广泛采用，导致隐私泄露。尽管已经提出了许多成本敏感的方法来应对多步攻击，但大多数研究缺乏全局优化，并且忽略了攻击者可能采取多条路径发起多步攻击的事实，这可能导致过度响应或反应不足。为了解决这个问题，我们将对多路径攻击的响应制定为一个优化问题，并证明它是 NP 难的。为了获得该问题的可行解决方案，我们首先识别可疑的攻击路径并评估对策的几个指标（即安全收益、部署成本和对服务质量的负面影响）。具体来说，通过考虑原子攻击的组成和覆盖度，我们定义了攻击面覆盖率，以准确评估对策的安全优势。然后，我们提出了一种改进的贪心算法来选择合理的对策。实验结果证明了我们方法的有效性和可行性。