CVE-2020-15113

In etcd before versions 3.3.23 and 3.4.10, certain directory paths are
created (etcd data directory and the directory path when provided to
automatically generate self-signed certificates for TLS connections with
clients) with restricted access permissions (700) by using the os.MkdirAll.
This function does not perform any permission checks when a given directory
path exists already. A possible workaround is to ensure the directories
have the desired permission (700).