IBM z/OS UNIX groups must be defined with a unique GID.
Overview
| Finding ID | Version | Rule ID | IA Controls | Severity |
| V-223857 | RACF-US-000200 | SV-223857r958482_rule | CCI-000764 | medium |
| Description | ||||
| To assure accountability and prevent unauthenticated access, organizational users must be identified and authenticated to prevent potential misuse and compromise of the system. RACF userid groups, and started tasks that use z/OS UNIX facilities are defined to an ACP with attributes including UID and GID. If these attributes are not correctly defined, data access or command privilege controls could be compromised. | ||||
| STIG | Date | |||
| IBM z/OS RACF Security Technical Implementation Guide | 2025-06-24 | |||
Details
Check Text (C-223857r958482_chk)
From ISPF Command Shell enter:
Listgrp * OMVS
If each group is defined with a unique GID, this is not a finding.
Note: A site can choose to have both an OMVSGRP group and an STCOMVS group or combine the groups under one of these names.
If OMVSGRP and/or STCOMVS groups are defined and have a unique GID in the range of 1-99, this is not a finding.
Fix Text (F-25518r868906_fix)
Define each UNIX group with a unique GID.
Define the OMVSGRP group and/or the STCOMVS group to the security database with a unique GID in the range of 1-99.
OMVSGRP is the name suggested by IBM for all the required userids. STCOMVS is the standard name used at some sites for the userids that are associated with z/OS UNIX started tasks and daemons. These groups can be combined at the site's discretion.