Improper Access Control
The File module in Drupal 7.x before 7.43 and 8.x before 8.0.4 allows remote authenticated users to bypass access restrictions and read, delete, or substitute a link to a file uploaded to an unprocessed form by leveraging permission to create content or comment and upload files.
CWE-284 - Improper Access Control
Listed 5th in the 'OWASP Top Ten', improper (or broken) access control attacks are a fundamental type of vulnerability. This includes a broad range of design flaws that enable users to act outside of their intended permissions. They can use these privileges to gain access to restricted files and functionality such as accessing restricted information, falsifying records, destroying data, or executing commands.