PostgreSQL must generate audit records showing starting and ending time for user access to the database(s).

Overview

Finding ID	Version	Rule ID	IA Controls	Severity
V-72925	PGS9-00-004700	SV-87577r2_rule		Medium

Description
For completeness of forensic analysis, it is necessary to know how long a user's (or other principal's) connection to PostgreSQL lasts. This can be achieved by recording disconnections, in addition to logons/connections, in the audit logs. Disconnection may be initiated by the user or forced by the system (as in a timeout) or result from a system or network failure. To the greatest extent possible, all disconnections must be logged.

Description

For completeness of forensic analysis, it is necessary to know how long a user's (or other principal's) connection to PostgreSQL lasts. This can be achieved by recording disconnections, in addition to logons/connections, in the audit logs. Disconnection may be initiated by the user or forced by the system (as in a timeout) or result from a system or network failure. To the greatest extent possible, all disconnections must be logged.

STIG	Date
PostgreSQL 9.x Security Technical Implementation Guide	2018-02-27

Details

Check Text ( C-73059r1_chk )
Note: The following instructions use the PGDATA environment variable. See supplementary content APPENDIX-F for instructions on configuring PGDATA. First, log into the database with the postgres user by running the following commands: $ sudo su - postgres $ psql -U postgres Next, as the database administrator, verify the log for a connection audit trail: $ sudo su - postgres $ cat ${PGDATA?}/pg_log/postgresql-Tue.log < 2016-02-23 20:25:39.931 EST postgres 56cfa993.7a72 postgres: >LOG: connection authorized: user=postgres database=postgres < 2016-02-23 20:27:45.428 EST postgres 56cfa993.7a72 postgres: >LOG: AUDIT: SESSION,1,1,READ,SELECT,,,SELECT current_user;, < 2016-02-23 20:27:47.988 EST postgres 56cfa993.7a72 postgres: >LOG: disconnection: session time: 0:00:08.057 user=postgres database=postgres host=[local] If connections are not logged, this is a finding.

Check Text ( C-73059r1_chk )

Note: The following instructions use the PGDATA environment variable. See supplementary content APPENDIX-F for instructions on configuring PGDATA.

First, log into the database with the postgres user by running the following commands:

$ sudo su - postgres
$ psql -U postgres

Next, as the database administrator, verify the log for a connection audit trail:

$ sudo su - postgres
$ cat ${PGDATA?}/pg_log/postgresql-Tue.log
< 2016-02-23 20:25:39.931 EST postgres 56cfa993.7a72 postgres: >LOG: connection authorized: user=postgres database=postgres
< 2016-02-23 20:27:45.428 EST postgres 56cfa993.7a72 postgres: >LOG: AUDIT: SESSION,1,1,READ,SELECT,,,SELECT current_user;,
< 2016-02-23 20:27:47.988 EST postgres 56cfa993.7a72 postgres: >LOG: disconnection: session time: 0:00:08.057 user=postgres database=postgres host=[local]

If connections are not logged, this is a finding.

Fix Text (F-79369r2_fix)
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 connections, date/time, username, and session identifier. First, as the database administrator (shown here as "postgres"), edit postgresql.conf by running the following: $ sudo su - postgres $ vi ${PGDATA?}/postgresql.conf Edit the following parameters: log_connections = on log_disconnections = 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

Fix Text (F-79369r2_fix)

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 connections, date/time, username, and session identifier.

First, as the database administrator (shown here as "postgres"), edit postgresql.conf by running the following:

$ sudo su - postgres
$ vi ${PGDATA?}/postgresql.conf

Edit the following parameters:

log_connections = on
log_disconnections = 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