IBM z/OS UNIX MVS data sets with z/OS UNIX components must be properly protected.

Overview

Finding ID	Version	Rule ID	IA Controls	Severity
V-98867	TSS0-US-000070	SV-107971r1_rule		Medium

Description
To mitigate the risk of unauthorized access to sensitive information by entities that have been issued certificates by DoD-approved PKIs, all DoD systems (e.g., web servers and web portals) must be properly configured to incorporate access control methods that do not rely solely on the possession of a certificate for access. Successful authentication must not automatically give an entity access to an asset or security boundary. Authorization procedures and controls must be implemented to ensure each authenticated entity also has a validated and current authorization. Authorization is the process of determining whether an entity, once authenticated, is permitted to access a specific asset. Information systems use access control policies and enforcement mechanisms to implement this requirement. Access control policies include: identity-based policies, role-based policies, and attribute-based policies. Access enforcement mechanisms include: access control lists, access control matrices, and cryptography. These policies and mechanisms must be employed by the application to control access between users (or processes acting on behalf of users) and objects (e.g., devices, files, records, processes, programs, and domains) in the information system. Satisfies: SRG-OS-000080-GPOS-00048, SRG-OS-000259-GPOS-00100

Description

To mitigate the risk of unauthorized access to sensitive information by entities that have been issued certificates by DoD-approved PKIs, all DoD systems (e.g., web servers and web portals) must be properly configured to incorporate access control methods that do not rely solely on the possession of a certificate for access. Successful authentication must not automatically give an entity access to an asset or security boundary. Authorization procedures and controls must be implemented to ensure each authenticated entity also has a validated and current authorization. Authorization is the process of determining whether an entity, once authenticated, is permitted to access a specific asset. Information systems use access control policies and enforcement mechanisms to implement this requirement. Access control policies include: identity-based policies, role-based policies, and attribute-based policies. Access enforcement mechanisms include: access control lists, access control matrices, and cryptography. These policies and mechanisms must be employed by the application to control access between users (or processes acting on behalf of users) and objects (e.g., devices, files, records, processes, programs, and domains) in the information system. Satisfies: SRG-OS-000080-GPOS-00048, SRG-OS-000259-GPOS-00100

STIG	Date
IBM z/OS TSS Security Technical Implementation Guide	2020-06-29

Details

Check Text ( C-97703r1_chk )
If the ESM data set rules for each of the data sets listed in the table below restrict WRITE or greater access to systems programming personnel, this is not a finding. MVS DATA SETS WITH z/OS UNIX COMPONENTS DATA SET NAME/MASK MAINTENANCE TYPE FUNCTION SYS1.ABPX* Distribution IBM z/OS UNIX ISPF panels, messages, tables, clists SYS1.AFOM* Distribution IBM z/OS UNIX Application Services SYS1.BPA.ABPA* Distribution IBM z/OS UNIX Connection Scaling Process Mgr. SYS1.CMX.ACMX* Distribution IBM z/OS UNIX Connection Scaling Connection Mgr. SYS1.SBPX* Target IBM z/OS UNIX ISPF panels, messages, tables, clists SYS1.SFOM* Target IBM z/OS UNIX Application Services SYS1.CMX.SCMX* Target IBM z/OS UNIX Connection Scaling Connection Mgr.

Check Text ( C-97703r1_chk )

If the ESM data set rules for each of the data sets listed in the table below restrict WRITE or greater access to systems programming personnel, this is not a finding.

MVS DATA SETS WITH z/OS UNIX COMPONENTS
DATA SET NAME/MASK MAINTENANCE TYPE FUNCTION
SYS1.ABPX* Distribution IBM z/OS UNIX ISPF panels, messages, tables, clists
SYS1.AFOM* Distribution IBM z/OS UNIX Application Services
SYS1.BPA.ABPA* Distribution IBM z/OS UNIX Connection Scaling Process Mgr.
SYS1.CMX.ACMX* Distribution IBM z/OS UNIX Connection Scaling Connection Mgr.
SYS1.SBPX* Target IBM z/OS UNIX ISPF panels, messages, tables, clists
SYS1.SFOM* Target IBM z/OS UNIX Application Services
SYS1.CMX.SCMX* Target IBM z/OS UNIX Connection Scaling Connection Mgr.

Fix Text (F-104543r1_fix)
Define ESM data set rules for each of the data sets listed in the table below restrict WRITE or greater access to systems programming personnel. MVS DATA SETS WITH z/OS UNIX COMPONENTS DATA SET NAME/MASK MAINTENANCE TYPE FUNCTION SYS1.ABPX* Distribution IBM z/OS UNIX ISPF panels, messages, tables, clists SYS1.AFOM* Distribution IBM z/OS UNIX Application Services SYS1.BPA.ABPA* Distribution IBM z/OS UNIX Connection Scaling Process Mgr. SYS1.CMX.ACMX* Distribution IBM z/OS UNIX Connection Scaling Connection Mgr. SYS1.SBPX* Target IBM z/OS UNIX ISPF panels, messages, tables, clists SYS1.SFOM* Target IBM z/OS UNIX Application Services SYS1.CMX.SCMX* Target IBM z/OS UNIX Connection Scaling Connection Mgr. The data sets designated as distribution data sets should have all access restricted to systems programming personnel. TSO/E users who also use z/OS UNIX should have read access to the SYS1.SBPX* data sets. Read access for all users to the remaining target data sets is at the site’s discretion. All other access must be restricted to systems programming personnel.

Fix Text (F-104543r1_fix)

Define ESM data set rules for each of the data sets listed in the table below restrict WRITE or greater access to systems programming personnel.

MVS DATA SETS WITH z/OS UNIX COMPONENTS
DATA SET NAME/MASK MAINTENANCE TYPE FUNCTION
SYS1.ABPX* Distribution IBM z/OS UNIX ISPF panels, messages, tables, clists
SYS1.AFOM* Distribution IBM z/OS UNIX Application Services
SYS1.BPA.ABPA* Distribution IBM z/OS UNIX Connection Scaling Process Mgr.
SYS1.CMX.ACMX* Distribution IBM z/OS UNIX Connection Scaling Connection Mgr.
SYS1.SBPX* Target IBM z/OS UNIX ISPF panels, messages, tables, clists
SYS1.SFOM* Target IBM z/OS UNIX Application Services
SYS1.CMX.SCMX* Target IBM z/OS UNIX Connection Scaling Connection Mgr.

The data sets designated as distribution data sets should have all access restricted to systems programming personnel. TSO/E users who also use z/OS UNIX should have read access to the SYS1.SBPX* data sets. Read access for all users to the remaining target data sets is at the site’s discretion. All other access must be restricted to systems programming personnel.