CWE-689 — Vulnerability Class 2

CWE-689 represents a permission race condition during resource copy, a critical weakness where a system fails to enforce access controls on a newly created file or directory until the copying process finishes. Attackers typically exploit this vulnerability by monitoring the target location and attempting to access or modify the partially copied resource before the final permission settings are applied. This window of exposure allows unauthorized users to read sensitive data or inject malicious content into the incomplete file. To mitigate this risk, developers must ensure that permissions are set atomically or immediately upon resource creation, rather than after the copy operation completes. Implementing secure temporary storage mechanisms and using atomic file operations can effectively prevent this race condition, ensuring that resources remain protected throughout their entire lifecycle from creation to finalization.