CWE-910 (使用过期的文件描述符) — Vulnerability Class 1

CWE-910 represents a resource management weakness where software incorrectly accesses a file descriptor after it has been closed. This vulnerability arises because operating systems often reuse file descriptor numbers for new resources, meaning the previously closed descriptor may now point to a completely different file or device. Attackers typically exploit this by triggering the closure and then manipulating the application to write to the reused descriptor, potentially leading to unauthorized data modification, information disclosure, or denial of service. To prevent this, developers must rigorously manage resource lifecycles by nullifying or invalidating pointers immediately after closing descriptors. Implementing strict state checks before any I/O operation and utilizing higher-level abstractions that handle resource cleanup automatically can significantly reduce the risk of accessing stale or reused file handles.