Details
extproc should be removed from the listener.ora to mitigate the risk that OS libraries can be invoked by the Oracle instance.
NOTE: ORACLE_HOME should be set to the appropriate directory based on the specifications of the organization.
Solution
Remove extproc from the listener.ora file.
Supportive Information
The following resource is also helpful.
This security hardening control applies to the following category of controls within NIST 800-53: Configuration Management.This control applies to the following type of system Unix.