A Memory Object Sensitive Detecting Method for Use-After-Free Vulnerabilities

The Use-After-Free vulnerability has drawn significant concern recently due to its widespread occurrence and harmful impact on applications, and detecting Use-After-Free and Double Free bugs is a critical challenge in software security. Current detection methods such as AddressSanitizer fail to detect Use-After-Free bugs caused by memory object reoccupation. In this paper, we propose a memory object sensitive detecting method for Use-After-Free vulnerabilities to handle the reoccupation problem. We firstly track the lifetime of memory object through runtime library, and then we construct a novel shadow memory to retain essential diagnosing data. To detect bugs, we label the pointer to the memory object and track the propagation process. Based on that, we implement a tool MOSan. Our experiments on CWE benchmark shows that MOSan could detect all Use-After-Free and Double Free bugs without any false negative, significantly surpassing the effectiveness of Asan.