Never keep an old and/or vulnerable version of pma on the webserver, visible to the web.
Or remove it, or move it to an area not reachable by the web.
Harassing old versions of phpMyAdmin, in searching for flaws/vulnerabilities, is the most common access on the web.
So, I suggest you replace:
mv pma pma2018
by:
mv pma ~/pma2018
Regards,
Netino