Title

PostgreSQL must generate audit records for all privileged activities or other system-level access. (Cat II impact)

Discussion

Without tracking privileged activity, it would be difficult to establish, correlate, and investigate the events relating to an incident or identify those responsible for one. System documentation should include a definition of the functionality considered privileged. A privileged function in this context is any operation that modifies the structure of the database, its built-in logic, or its security settings. This would include all Data Definition Language (DDL) statements and all security-related statements. In a SQL environment, it encompasses, but is not necessarily limited to: CREATE ALTER DROP GRANT REVOKE There may also be Data Manipulation Language (DML) statements that, subject to context, should be regarded as privileged. Possible examples in SQL include: TRUNCATE TABLE, DELETE, or DELETE affecting more than n rows, for some n, or DELETE without a WHERE clause. UPDATE or UPDATE affecting more than n rows, for some n, or UPDATE without a WHERE clause. Any SELECT, INSERT, UPDATE, or DELETE to an application-defined security table executed by other than a security principal. Depending on the capabilities of PostgreSQL and the design of the database and associated applications, audit logging may be achieved by means of DBMS auditing features, database triggers, other mechanisms, or a combination of these. Note: It is particularly important to audit, and tightly control, any action that weakens the implementation of this requirement itself, since the objective is to have a complete audit trail of all administrative activity.

Check Content

First, as the database administrator, verify pgaudit is enabled by running the following SQL: $ sudo su - postgres $ psql -c "SHOW shared_preload_libraries" If the output does not contain pgaudit, this is a finding. Next, verify that role, read, write, and ddl auditing are enabled: $ psql -c "SHOW pgaudit.log" If the output does not contain role, read, write, and ddl, this is a finding.

Fix Text

Note: The following instructions use the PGDATA and PGVER environment variables. See supplementary content APPENDIX-F for instructions on configuring PGDATA and APPENDIX-H for PGVER. Using pgaudit PostgreSQL can be configured to audit these requests. See supplementary content APPENDIX-B for documentation on installing pgaudit. With pgaudit installed the following configurations can be made: $ sudo su - postgres $ vi ${PGDATA?}/postgresql.conf Add the following parameters (or edit existing parameters): shared_preload_libraries = 'pgaudit' pgaudit.log='ddl, role, read, write' Now, as the system administrator, reload the server with the new configuration: $ sudo systemctl reload postgresql-${PGVER?}

Additional Identifiers

Rule ID: SV-233565r879875_rule

Vulnerability ID: V-233565

Group Title: SRG-APP-000504-DB-000354

Expert Comments

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