z/OS UNIX security parameters for restricted network service(s) in /etc/inetd.conf are not properly specified.

Overview

Finding ID	Version	Rule ID	IA Controls	Severity
V-6947	ZUSS0014	SV-7248r2_rule	DCCS-1 DCCS-2	Medium

Description
Parameter settings in PARMLIB and /etc specify values for z/OS UNIX security controls. The parameters impact HFS data access and operating system services. Undesirable values can allow users to gain inappropriate privileges that could impact data integrity or the availability of some system services.

STIG	Date
z/OS TSS STIG	2019-12-12

Details

Check Text ( C-22297r1_chk )
a) Refer to the following reports produced by the UNIX System Services Data Collection: - USSCMDS.RPT(EINETD) - USSCMDS.RPT(ESERV) b) If all the services in the Restricted Network Services Table in the z/OS STIG Addendum are not found in or are commented out of the /etc/inetd.conf file, there is NO FINDING. c) If any Restricted Network Services are specified, this is a FINDING.

Fix Text (F-6717r1_fix)
Review the settings in The /etc/inetd.conf file determine if every entry in the file represents a service that is actually in use. Services that are not in use must be disabled to reduce potential security exposures. The following services must be disabled in /etc/inetd.conf unless justified and documented with the IAO: RESTRICTED NETWORK SERVICES Service Port Chargen 19 Daytime 13 Discard 9 Echo 7 Exec 512 finger 79 shell 514 time 37 login 513 smtp 25 timed 525 nameserver 42 systat 11 uucp 540 netstat 15 talk 517 qotd 17 tftp 69 /etc/inetd.conf The /etc/inetd.conf file is used by the INETD daemon. It specifies how INETD is to handle service requests on network sockets. Specifically, there is one entry in inetd.conf for each service. Each service entry specifies several parameters. The login_name parameter is of special interest. It specifies the userid under which the forked daemon is to execute. This userid is defined to the ACP and it may require a UID(0) (i.e., superuser authority) value.

Fix Text (F-6717r1_fix)

Review the settings in The /etc/inetd.conf file determine if every entry in the file represents a service that is actually in use. Services that are not in use must be disabled to reduce potential security exposures.
The following services must be disabled in /etc/inetd.conf unless justified and documented with the IAO:

RESTRICTED NETWORK SERVICES

Service Port
Chargen 19
Daytime 13
Discard 9
Echo 7
Exec 512
finger 79
shell 514
time 37
login 513
smtp 25
timed 525
nameserver 42
systat 11
uucp 540
netstat 15
talk 517
qotd 17
tftp 69

/etc/inetd.conf
The /etc/inetd.conf file is used by the INETD daemon. It specifies how INETD is to handle service requests on network sockets. Specifically, there is one entry in inetd.conf for each service. Each service entry specifies several parameters. The login_name parameter is of special interest. It specifies the userid under which the forked daemon is to execute. This userid is defined to the ACP and it may require a UID(0) (i.e., superuser authority) value.