CA-TSS must limit access to the System Master Catalog to appropriate authorized users.

Overview

Finding ID	Version	Rule ID	IA Controls	Severity
V-223904	TSS0-ES-000310	SV-223904r877745_rule		High

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-000324-GPOS-00125

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-000324-GPOS-00125

STIG	Date
IBM z/OS TSS Security Technical Implementation Guide	2024-02-22

Details

Check Text ( C-25577r868930_chk )
Refer to SYSCATxx member of SYS1.NUCLEUS. Multiple SYSCATxx members may be defined; if so, refer to Master Catalog message for IPL. If the member is not found, refer to the appropriate LOADxx member of SYS1.PARMLIB. If data set rules for the Master Catalog do not restrict greater than "READ" access to only z/OS systems programming personnel, this is a finding. If products or procedures requiring system programmer access for system-level maintenance meet the following specific case, this is not a finding: - The batch job or procedure must be documented in the SITE Security Plan. - Reside in a data set that is restricted to systems programmers' access only. If data set rules for the Master Catalog do not specify that all (i.e., failures and successes) greater than "READ" access will be logged, this is a finding.

Check Text ( C-25577r868930_chk )

Refer to SYSCATxx member of SYS1.NUCLEUS.

Multiple SYSCATxx members may be defined; if so, refer to Master Catalog message for IPL.

If the member is not found, refer to the appropriate LOADxx member of SYS1.PARMLIB.

If data set rules for the Master Catalog do not restrict greater than "READ" access to only z/OS systems programming personnel, this is a finding.

If products or procedures requiring system programmer access for system-level maintenance meet the following specific case, this is not a finding:
- The batch job or procedure must be documented in the SITE Security Plan.
- Reside in a data set that is restricted to systems programmers' access only.

If data set rules for the Master Catalog do not specify that all (i.e., failures and successes) greater than "READ" access will be logged, this is a finding.

Fix Text (F-25565r868931_fix)
Review access authorization to critical system files. Evaluate the impact of correcting the deficiency. Develop a plan of action and implement the changes as required to protect the MASTER CATALOG. Configure the ESM rules for system catalog to only allow access above "READ" to systems programmers and those authorized by the ISSM/ISSO. Configure ESM rules for the master catalog to allow access above "READ" to systems programmers ONLY. Configure ESM rules for the master catalog to allow any products or procedures system programmer access for system-level maintenance that meet the following specific case: - The batch job or procedure must be documented in the SITE Security Plan. - Reside in a data set that is restricted to systems programmers' access only. All greater than read access must be logged.

Fix Text (F-25565r868931_fix)

Review access authorization to critical system files.

Evaluate the impact of correcting the deficiency.

Develop a plan of action and implement the changes as required to protect the MASTER CATALOG.

Configure the ESM rules for system catalog to only allow access above "READ" to systems programmers and those authorized by the ISSM/ISSO.

Configure ESM rules for the master catalog to allow access above "READ" to systems programmers ONLY.

Configure ESM rules for the master catalog to allow any products or procedures system programmer access for system-level maintenance that meet the following specific case:
- The batch job or procedure must be documented in the SITE Security Plan.
- Reside in a data set that is restricted to systems programmers' access only.

All greater than read access must be logged.