The MODE Control Option must be set to (FAIL).

Overview

Finding ID	Version	Rule ID	IA Controls	Severity
V-205	TSS0460	SV-205r3_rule		High

Description
The MODE Control Option selects the security mode in which TSS will operate for all facilities. The system-wide options control the default settings for determining how the ACP will function when handling requests for access to the operating system environment, ACP, and customer data. The ACP provides the ability to set a number of these fields at the subsystem level. If no setting is found, the system-wide defaults will be used. The improper setting of any of these fields, individually or in combination with another, can compromise the security of the processing environment. In addition, failure to establish standardized settings for the ACP control options introduces the possibility of exposure during migration process or contingency plan activation.

Description

The MODE Control Option selects the security mode in which TSS will operate for all facilities. The system-wide options control the default settings for determining how the ACP will function when handling requests for access to the operating system environment, ACP, and customer data. The ACP provides the ability to set a number of these fields at the subsystem level. If no setting is found, the system-wide defaults will be used. The improper setting of any of these fields, individually or in combination with another, can compromise the security of the processing environment. In addition, failure to establish standardized settings for the ACP control options introduces the possibility of exposure during migration process or contingency plan activation.

STIG	Date
z/OS TSS STIG	2018-12-20

Details

Check Text ( C-458r2_chk )
a) Refer to the following reports produced by the TSS Data Collection: - TSSCMDS.RPT(STATUS) Automated Analysis requires Additional Analysis. Refer to the following report produced by the TSS Data Collection: - PDI(TSS0460) b) If the global MODE Control Option value is set to FAIL, there is NO FINDING. c) If the global MODE Control Option value is not set to FAIL, this is a FINDING. Additional analysis may be required under the following conditions: 1) Examples of a Category I FINDING where no further analysis is required: Control Options: MODE (DORMANT) MODE (WARN) 2) Example of a possible Category I FINDING requiring additional analysis: Control Options: MODE (IMPL) MODE(IMPL) allows access to a data set and resource only when it is not defined to TSS. Therefore if all sensitive data sets and resources are properly defined to the security database, MODE(IMPL) will not allow unauthorized access.

Check Text ( C-458r2_chk )

a) Refer to the following reports produced by the TSS Data Collection:

- TSSCMDS.RPT(STATUS)

Automated Analysis requires Additional Analysis.
Refer to the following report produced by the TSS Data Collection:

- PDI(TSS0460)

b) If the global MODE Control Option value is set to FAIL, there is NO FINDING.

c) If the global MODE Control Option value is not set to FAIL, this is a FINDING. Additional analysis may be required under the following conditions:

1) Examples of a Category I FINDING where no further analysis is required:

Control Options: MODE (DORMANT)
MODE (WARN)

2) Example of a possible Category I FINDING requiring additional analysis:

Control Options: MODE (IMPL)

MODE(IMPL) allows access to a data set and resource only when it is not defined to TSS. Therefore if all sensitive data sets and resources are properly defined to the security database, MODE(IMPL) will not allow unauthorized access.

Fix Text (F-17142r1_fix)
Evaluate the impact associated with implementation of the control option. Develop a plan of action to set the MODE control option to (FAIL) and proceed with the change.