STIGQter: STIG Summary: IBM z/OS TSS Security Technical Implementation Guide Version: 8 Release: 2 Benchmark Date: 23 Apr 2021:

IBM z/OS attributes of UNIX user accounts used for account modeling must be defined in accordance with security requirements.

DISA Rule

SV-224098r561402_rule

Vulnerability Number

V-224098

Group Title

SRG-OS-000104-GPOS-00051

Rule Version

TSS0-US-000250

Severity

CAT II

CCI(s)

CCI-000764 - The information system uniquely identifies and authenticates organizational users (or processes acting on behalf of organizational users).

Weight

Fix Recommendation

Use of the OMVS default UID will not be allowed on any classified system.

Define the user identifier (ACID) used to model OMVS user account with a non-writable home directory, such as "\" root, and a non-executable, but existing, binary file, "/bin/false" or "/bin/echo."

Check Contents

From the ISPF Command Shell enter:
TSS LIST(ACIDS) DATA(NAME) SEGMENT(OMVS)
This check applies to any user identifier (ACID) used to model OMVS access on the mainframe. This includes OMVSUSR; MODLUSER, and BPX.UNIQUE.USER.
ENTER
TSS MODIFY STATUS

If ANY MODLUSER is specified then UNIQUSER must be specified as "ON" in the STATUS.

If user identifier (ACID) used to model OMVS user account is defined as follows, this is not finding.

A non-writable HOME directory
Shell program specified as "/bin/echo", or "/bin/false"

Note: The shell program must have one of the specified values. The HOME directory must have a value (i.e., not be allowed to default).

IBM z/OS attributes of UNIX user accounts used for account modeling must be defined in accordance with security requirements.

DISA Rule

Vulnerability Number

Group Title

Rule Version

Severity

CCI(s)

Weight

Fix Recommendation

Check Contents

Vulnerability Number

Documentable

Rule Version

Severity Override Guidance

Check Content Reference

Target Key

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