PostgreSQL must generate audit records when unsuccessful logons or connection attempts occur.
Overview
| Finding ID | Version | Rule ID | IA Controls | Severity |
| V-261957 | CD16-00-011300 | SV-261957r1000876_rule | CCI-000172 | medium |
| Description | ||||
| 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. | ||||
| STIG | Date | |||
| Crunchy Data Postgres 16 Security Technical Implementation Guide | 2024-06-17 | |||
Details
Check Text (C-261957r1000876_chk)
Note: The following instructions use the PGDATA and PGLOG environment variables. Refer to APPENDIX-F for instructions on configuring PGDATA and APPENDIX-I on PGLOG.
In this example the user "joe" will log in to the Postgres database unsuccessfully:
$ psql -d postgres -U joe
As the database administrator (shown here as "postgres"), check ${PGLOG?} for a FATAL connection audit trail:
$ sudo su - postgres
$ cat ${PGDATA?}/${PGLOG?}/{latest_log>
< 2024-02-16 16:18:13.027 UTC joe 56c65135.b5f postgres: >LOG: connection authorized: user=joe database=postgres
< 2024-02-16 16:18:13.027 UTC 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 (F-65719r1000875_fix)
Note: The following instructions use the PGDATA and PGVER environment variables. Refer to APPENDIX-F for instructions on configuring PGDATA and APPENDIX-H for PGVER.
To ensure logging is enabled, see the instructions in the supplementary content APPENDIX-C.
If logging is enabled the following configurations must be made to log unsuccessful connections, date/time, username, and session identifier.
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
As the system administrator, reload the server with the new configuration:
$ sudo systemctl reload postgresql-${PGVER?}