DB2 must generate audit records when privileges/permissions are deleted.

Overview

Finding ID	Version	Rule ID	IA Controls	Severity
V-74637	DB2X-00-010800	SV-89311r1_rule		Medium

Description
Changes in the permissions, privileges, and roles granted to users and roles must be tracked. Without an audit trail, unauthorized elevation or restriction of individuals' and groups' privileges could go undetected. Elevated privileges give users access to information and functionality that they should not have; restricted privileges wrongly deny access to authorized users. In an SQL environment, deleting permissions is typically done via the REVOKE command.

Description

Changes in the permissions, privileges, and roles granted to users and roles must be tracked. Without an audit trail, unauthorized elevation or restriction of individuals' and groups' privileges could go undetected. Elevated privileges give users access to information and functionality that they should not have; restricted privileges wrongly deny access to authorized users. In an SQL environment, deleting permissions is typically done via the REVOKE command.

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

Details

Check Text ( C-74523r1_chk )
To meet these requirements at the SECMAINT, CONTEXT category auditing needs to be implemented at database level. Run the following SQL statement to ensure that an audit policy is defined upon the database: DB2> SELECT AUDITPOLICYNAME, AUDITPOLICYID FROM SYSCAT.AUDITUSE WHERE OBJECTTYPE IN (' ') If no rows are returned, this is a finding. Using the AUDITPOLICYID from above query find the details of audit policy: DB2> SELECT AUDITPOLICYNAME, CONTEXTSTATUS, SECMAINTSTATUS, ERRORTYPE AS ERRORTYPE FROM SYSCAT.AUDITPOLICIES WHERE AUDITPOLICYID = If the values for CONTEXTSTATUS and SECMAINTSTATUS are not 'B' (Both) or ERRORTYPE is not 'A' (Audit), this is a finding.

Check Text ( C-74523r1_chk )

To meet these requirements at the SECMAINT, CONTEXT category auditing needs to be implemented at database level.

Run the following SQL statement to ensure that an audit policy is defined upon the database:
DB2> SELECT AUDITPOLICYNAME, AUDITPOLICYID
FROM SYSCAT.AUDITUSE
WHERE OBJECTTYPE IN (' ')

If no rows are returned, this is a finding.

Using the AUDITPOLICYID from above query find the details of audit policy:
DB2> SELECT AUDITPOLICYNAME, CONTEXTSTATUS, SECMAINTSTATUS, ERRORTYPE AS ERRORTYPE
FROM SYSCAT.AUDITPOLICIES
WHERE AUDITPOLICYID =

If the values for CONTEXTSTATUS and SECMAINTSTATUS are not 'B' (Both) or ERRORTYPE is not 'A' (Audit), this is a finding.

Fix Text (F-81237r1_fix)
Run the following command to define an audit policy with the needed subset using the CREATE AUDIT POLICY SQL statement: DB2> CREATE AUDIT POLICY CATEGORIES SECMAINT STATUS BOTH, CONTEXT STATUS BOTH ERROR TYPE AUDIT To modify an existing audit policy, replace "CREATE" with "ALTER" in the preceding statement. Only the categories explicitly named in the statement will be affected. In this case, the changes take effect immediately. If CREATE was used above, in the following command to apply the policy created above to the database: DB2> AUDIT DATABASE USING POLICY

Fix Text (F-81237r1_fix)

Run the following command to define an audit policy with the needed subset using the CREATE AUDIT POLICY SQL statement:
DB2> CREATE AUDIT POLICY
CATEGORIES SECMAINT STATUS BOTH, CONTEXT STATUS BOTH
ERROR TYPE AUDIT

To modify an existing audit policy, replace "CREATE" with "ALTER" in the preceding statement. Only the categories explicitly named in the statement will be affected. In this case, the changes take effect immediately.

If CREATE was used above, in the following command to apply the policy created above to the database:
DB2> AUDIT DATABASE USING POLICY