Ensure NIS Client is not installed - dpkg

Information

The NIS service is inherently an insecure system that has been vulnerable to DOS attacks, buffer overflows and has poor authentication for querying NIS maps. NIS generally has been replaced by such protocols as Lightweight Directory Access Protocol (LDAP). It is recommended that the service be removed.

Solution

Uninstall ypbind using the appropriate package manager or manual installation:
yum remove ypbind
apt-get remove ypbind
zypper remove ypbind

See Also

https://www.cisco.com/c/en/us/td/docs/security/firepower/623/configuration/guide/fpmc-config-guide-v623.html