Title

PostgreSQL must generate audit records when unsuccessful logons or connection attempts occur. (Cat II impact)

Discussion

For completeness of forensic analysis, it is necessary to track failed attempts to log on to PostgreSQL. While positive identification may not be possible in a case of failed authentication, as much information as possible about the incident must be captured.

Check Content

Note: The following instructions use the PGDATA environment variable. See supplementary content APPENDIX-F for instructions on configuring PGDATA. In this example the user joe will log into the Postgres database unsuccessfully: $ psql -d postgres -U joe As the database administrator (shown here as "postgres"), check pg_log for a FATAL connection audit trail: $ sudo su - postgres $ cat ${PGDATA?}/pg_log/postgresql-Tue.log < 2016-02-16 16:18:13.027 EST joe 56c65135.b5f postgres: >LOG: connection authorized: user=joe database=postgres < 2016-02-16 16:18:13.027 EST joe 56c65135.b5f postgres: >FATAL: role "joe" does not exist If an audit record is not generated each time a user (or other principal) attempts, but fails to log on or connect to PostgreSQL (including attempts where the user ID is invalid/unknown), 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. To ensure that logging is enabled, review supplementary content APPENDIX-C for instructions on enabling logging. If logging is enabled the following configurations must be made to log unsuccessful connections, date/time, username, and session identifier. First, as the database administrator (shown here as "postgres"), edit postgresql.conf: $ sudo su - postgres $ vi ${PGDATA?}/postgresql.conf Edit the following parameters: log_connections = on log_line_prefix = '< %m %u %c: >' Where: * %m is the time and date * %u is the username * %c is the session ID for the connection Now, as the system administrator, reload the server with the new configuration: # SYSTEMD SERVER ONLY $ sudo systemctl reload postgresql-${PGVER?} # INITD SERVER ONLY $ sudo service postgresql-${PGVER?} reload

Additional Identifiers

Rule ID: SV-214087r879874_rule

Vulnerability ID: V-214087

Group Title: SRG-APP-000503-DB-000351

Expert Comments

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