Centos tmp folder is dangerous specially if you using webmin with it. To secure I followed this example. Please make copy of files before you edit it.
nano -w /etc/fstab
Now we need to create a new line, so navigate to the bottom of the file using your arrow key’s and append the following line, I recommend copying & pasting to ensure you don’t get it wrong.
none /tmp tmpfs nodev,nosuid,noexec,size=2GB 0 0