基于Pi演算的Android App权限提升攻击检测

针对Android App权限提升攻击的问题，基于Pi演算构建了一个形式化的权限提升攻击检测模型。利用扩展后的Pi演算对Android App及其运行时环境进行建模，得到形式化的行为模型；通过将权限安全策略形式化的表示为包含进程表达式的IF-THEN规则，并利用Pi演算的性质进行进程演算和迁移，构建了检测模型，并给出了权限提升攻击检测的方法。理论分析和实验表明，该方法具有线性的时间和空间复杂度，并可以非常容易地将现有的权限安全策略应用在该模型中，保证了模型的精确性。相比其他方法，该方法在提高检测精确性的同时并没有牺牲检测的效率。

Privilege escalation attacks detection for Android App based on Pi calculus

To solve the privilege escalation attacks on Android App, this paper proposed a formal privilege escalation attacks detection model based on Pi calculus. It used the extended Pi calculus to model the Android App and its runtime environment, and obtained a formal behavior model. By formalizing the privilege security policy as process expressions containing the IF-THEN rule and using the properties of Pi calculus to perform process calculus and migration, it constructed the detection model, and gave out the privilege escalation attacks detection method. The analysis and experiment results show that this method has linear time and space complexity, moreover, the existing privilege security policy can be easily applied on this model to ensure the accuracy of the model. Compared with other methods, the detection accuracy is improved without sacrificing the detection efficiency.