DB2 must protect against a user falsely repudiating having performed organization-defined actions.

Overview

Finding ID	Version	Rule ID	IA Controls	Severity
V-74435	DB2X-00-000500	SV-89109r1_rule		Medium

Description
Non-repudiation of actions taken is required in order to maintain data integrity. Examples of particular actions taken by individuals include creating information, sending a message, approving information (e.g., indicating concurrence or signing a contract), and receiving a message. Non-repudiation protects against later claims by a user of not having created, modified, or deleted a particular data item or collection of data in the database. In designing a database, the organization must define the types of data and the user actions that must be protected from repudiation. The implementation must then include building audit features into the application data tables, and configuring the DBMS' audit tools to capture the necessary audit trail. Design and implementation also must ensure that applications pass individual user identification to the DBMS, even where the application connects to the DBMS with a standard, group account.

Description

Non-repudiation of actions taken is required in order to maintain data integrity. Examples of particular actions taken by individuals include creating information, sending a message, approving information (e.g., indicating concurrence or signing a contract), and receiving a message. Non-repudiation protects against later claims by a user of not having created, modified, or deleted a particular data item or collection of data in the database. In designing a database, the organization must define the types of data and the user actions that must be protected from repudiation. The implementation must then include building audit features into the application data tables, and configuring the DBMS' audit tools to capture the necessary audit trail. Design and implementation also must ensure that applications pass individual user identification to the DBMS, even where the application connects to the DBMS with a standard, group account.

STIG	Date
IBM DB2 V10.5 LUW Security Technical Implementation Guide	2019-09-27

Details

Check Text ( C-74361r1_chk )
Run the following SQL statement to ensure that an audit policy is defined upon all the required application tables and/or the database: DB2> SELECT AUDITPOLICYNAME, OBJECTSCHEMA, OBJECTNAME, OBJECTTYPE FROM SYSCAT.AUDITUSE WHERE OBJECTTYPE IN ('T',' ') If no rows are returned, this is a finding. If a row with OBJECTTYPE of ' ' (Database; value is a blank) exists in the output, it is a database level policy. If a row with OBJECTTYPE of 'T' exists in the output, it is a table level policy. For each audit policy returned in the statement above, run the following SQL statement to confirm that the CONTEXT and EXECUTE categories are part of that policy: DB2> SELECT AUDITPOLICYNAME, CONTEXTSTATUS, EXECUTESTATUS, ERRORTYPE AS ERRORTYPE FROM SYSCAT.AUDITPOLICIES If the database audit policy has the values for the CONTEXTSTATUS and EXECUTESTATUS columns set to 'S' (Success) or 'B' (Both) as well as the value in the ERRORTYPE column set to 'A' (Audit), this is not a finding. If the database policy does not exist or does not cover CONTEXTSTATUS or EXECUTESTATUS then check if the appropriate policies are defined for all the required application tables. If all the required application table audit policies do not have the values for the CONTEXTSTATUS and EXECUTESTATUS columns set to 'S' (Success) or 'B' (Both) as well as the value in the ERRORTYPE column set to 'A' (Audit), this is a finding.

Check Text ( C-74361r1_chk )

Run the following SQL statement to ensure that an audit policy is defined upon all the required application tables and/or the database:
DB2> SELECT AUDITPOLICYNAME, OBJECTSCHEMA, OBJECTNAME, OBJECTTYPE
FROM SYSCAT.AUDITUSE
WHERE OBJECTTYPE IN ('T',' ')

If no rows are returned, this is a finding.

If a row with OBJECTTYPE of ' ' (Database; value is a blank) exists in the output, it is a database level policy.

If a row with OBJECTTYPE of 'T' exists in the output, it is a table level policy.

For each audit policy returned in the statement above, run the following SQL statement to confirm that the CONTEXT and EXECUTE categories are part of that policy:
DB2> SELECT AUDITPOLICYNAME, CONTEXTSTATUS, EXECUTESTATUS, ERRORTYPE AS ERRORTYPE
FROM SYSCAT.AUDITPOLICIES

If the database audit policy has the values for the CONTEXTSTATUS and EXECUTESTATUS columns set to 'S' (Success) or 'B' (Both) as well as the value in the ERRORTYPE column set to 'A' (Audit), this is not a finding.

If the database policy does not exist or does not cover CONTEXTSTATUS or EXECUTESTATUS then check if the appropriate policies are defined for all the required application tables.

If all the required application table audit policies do not have the values for the CONTEXTSTATUS and EXECUTESTATUS columns set to 'S' (Success) or 'B' (Both) as well as the value in the ERRORTYPE column set to 'A' (Audit), this is a finding.

Fix Text (F-81035r1_fix)

Define the audit policy using the following Create Audit Policy SQL statement:
DB2> CREATE AUDIT POLICY
CATEGORIES CONTEXT STATUS BOTH, EXECUTE STATUS BOTH
ERROR TYPE AUDIT

Apply such a policy to either the database as a whole or to the specific application tables using one of these two statements:
DB2> AUDIT DATABASE USING POLICY
Or
DB2> AUDIT TABLE USING POLICY

Note : While DB2 does provide basic audit capabilities, IBM highly recommends investing in and using a dedicated enterprise audit tool such as the IBM Security Guardium Data Activity Monitor in order to provide a comprehensive audit solution.