Amazon S3 for Craft CMS has an Information Disclosure vulnerability
Unauthenticated users can view a list of buckets the plugin has access to. The BucketsController->actionLoadBucketData() endpoint allows unauthenticated users with a valid CSRF token to view a list of buckets that the plugin is allowed to see. Users should update to version 2.2.5 of the plugin to mitigate the issue.