Docker is not safe for untrusted code. If the client can get local root privileges (e.g. CVE-2014-4699, CVE-2014-4014, CVE-2014-0196, unix-privesc-check, many m

Docker is not safe for untrusted code. If the client can get local root privileges (e.g. CVE-2014-4699, CVE-2014-4014, CVE-2014-0196, unix-privesc-check, many more) they can then escape the docker container. But it's definitely better than running as your own user!