Web Servers can use a file called /robot(s).txt to ask search engines to ignore certain files and directories. By nature this file can not be used to protect private files from public read access.

Review the content of the robots file and consider removing the files from the server or protect them in other ways in case you actually intended non-public availability.

Any serious web search engine will honor the /robot(s).txt file and not scan the files and directories listed there. Any entries listed in this file are not even hidden anymore.