Stealthy attacks have become a major threat to cybersecurity. Previous works in this direction fail to capture the practical resource constraints and mainly focus on one-node settings. In this article, we propose a two-player game-theoretic model, including a system of multiple independent nodes, a stealthy attacker, and an observable defender. In our model, the attacker can fully observe the defender's behavior and the system state, whereas the defender has zero feedback information. Furthermore, a strict resource constraint is introduced to limit the frequency of the attacks/defenses for both players. We characterize the best responses for both attacker and defender under both nonadaptive and adaptive strategies. We then study the sequential game where the defender first announces its strategy and the attacker then responds accordingly. We have designed an algorithm that finds a nearly optimal strategy for the defender and provides a full analysis of its complexity and performance guarantee.

中文翻译：

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防御资源有限的多个节点的隐身攻击：博弈论分析

隐身攻击已成为对网络安全的主要威胁。以前在这个方向上的工作未能捕获实际的资源限制，而主要集中在单节点设置上。在本文中，我们提出了一个两人游戏理论模型，包括一个由多个独立节点组成的系统，一个隐身的攻击者和一个可观察的防御者。在我们的模型中，攻击者可以完全观察防御者的行为和系统状态，而防御者具有零反馈信息。此外，引入了严格的资源约束以限制两个玩家的进攻/防守的频率。在非自适应和自适应策略下，我们都将为攻击者和防御者提供最佳响应。然后，我们研究连续游戏，在该游戏中，防御者首先宣布其策略，然后攻击者做出相应的响应。