IBM z/OS UNIX OMVS parameters in PARMLIB must be properly specified.

Severity	Group ID	Group Title	Version	Rule ID	Date	STIG Version
medium	V-223629	SRG-OS-000480-GPOS-00227	ACF2-US-000140	SV-223629r991589_rule	2025-03-11	9

Description
Configuring the operating system to implement organization-wide security implementation guides and security checklists ensures compliance with federal standards and establishes a common security baseline across DoD that reflects the most restrictive security posture consistent with operational requirements.

ℹ️ Check
Refer to the IEASYS00 member of SYS1.PARMLIB. If the parameter is specified as OMVS=xx or OMVS=(xx,xx,...) in the IEASYSxx member, this is not a finding. If the OMVS statement is not specified, OMVS=DEFAULT is used. In minimum mode there is no access to permanent file systems or to the shell, and IBM's Communication Server TCP/IP will not run.

✔️ Fix
Configure the settings in PARMLIB and /etc for z/OS UNIX security parameters with values that conform to the specifications below: The parameter is specified as OMVS=xx or OMVS=(xx,xx,...) in the IEASYSxx member. Note: If the OMVS statement is not specified, OMVS=DEFAULT is used. In minimum mode there is no access to permanent file systems or to the shell, and IBM's Communication Server TCP/IP will not run.

✔️ Fix

Configure the settings in PARMLIB and /etc for z/OS UNIX security parameters with values that conform to the specifications below: The parameter is specified as OMVS=xx or OMVS=(xx,xx,...) in the IEASYSxx member. Note: If the OMVS statement is not specified, OMVS=DEFAULT is used. In minimum mode there is no access to permanent file systems or to the shell, and IBM's Communication Server TCP/IP will not run.