Vulnerability Advisory : File Browser has an Access Rule Bypass via Path Traversal in Copy/Rename Destination Parameter with LOW Attack Complexity

File Browser is a file managing interface for uploading, deleting, previewing, renaming, and editing files within a specified directory. Versions 2.61.2 and below are vulnerable to Path Traversal through the resourcePatchHandler (http/resource.go). The destination path in resourcePatchHandler is validated against access rules before being cleaned/normalized, while the actual file operation calls path.Clean() afterward—resolving .. sequences into a different effective path. This allows an authenticated user with Create or Rename permissions to bypass administrator-configured deny rules (both prefix-based and regex-based) by injecting .. sequences in the destination parameter of a PATCH request. As a result, the user can write or move files into any deny-rule-protected path within their scope. However, this cannot be used to escape the user's BasePathFs scope or read from restricted paths. This issue has been fixed in version 2.62.0.