OpenList: Search metadata/count disclosure via Non-Separator-Aware Path Check in Bleve Search

OpenList is a file list program that supports multiple storage backends. Prior to 4.2.4, the OpenList search API uses a non-separator-aware strings.HasPrefix comparison as a path containment authorization check when authorizing globally indexed Bleve results against a restricted user's BasePath. When Bleve search is enabled and a restricted authenticated user searches the global index for content in a sibling path, the user causes a globally indexed sibling-path result to pass the prefix check. The strings.HasPrefix(node.Parent, user.BasePath) predicate allows a sibling path such as /base2 to be treated as contained by /base. Unauthorized file metadata or file-existence information can be disclosed, and the backend Total value can reveal a match even when another access check removes the individual result. This issue is fixed in version 4.2.4.