Title

z/OS UNIX user accounts are not properly defined. (Cat II impact)

Discussion

User identifiers (ACF2 logonids, RACF userids, and Top Secret ACIDs), 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.

Check Content

a) Refer to the following report produced by the ACP Data Collection: ACF2 - ACF2CMDS.RPT(OMVSUSER) RACF - RACFCMDS.RPT(LISTUSER) TSS - TSSCMDS.RPT(OMVSUSER) NOTE: This check only applies to users of z/OS UNIX (i.e., users with an OMVS profile defined). b) If each user account is defined as follows, there is NO FINDING: 1) A unique UID number (except for UID(0) users) 2) A unique HOME directory (except for UID(0) and other system task accounts) 3) Shell program specified as “/bin/sh”, “/bin/tcsh”, “/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). c) If any user account is not defined as specified in (b) above, this is a FINDING.

Fix Text

The systems programmer will verify that each user account is defined as specified below: NOTE: This check only applies to users of z/OS UNIX (i.e., users with an OMVS profile defined). 1) A unique UID number (except for UID(0) users) 2) A unique HOME directory (except for UID(0) and other system task accounts) 3) Shell program specified as “/bin/sh”, “/bin/tcsh”, “/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).

Additional Identifiers

Rule ID: SV-7295r2_rule

Vulnerability ID: V-6992

Group Title: ZUSS0047

Expert Comments

CCIs tied to check.

Controls tied to check. These are derived from the CCIs shown above.