4.05 init.ora - 'remote_listener = NULL String'

Information

Prevent the use of a listener on a remote machine separate from the database instance.
Level 1, Scorable
NOTE: Change ORACLE_HOME to the full path to your organization's Oracle directory.
ref: https://benchmarks.cisecurity.org/tools2/oracle/CIS_Oracle_11g_Benchmark_v1.0.1.pdf, pg 32.