PostgreSQL must generate audit records when concurrent logons/connections by the same user from different workstations occur.

Overview

Finding ID	Version	Rule ID	IA Controls	Severity
V-72961	PGS9-00-006200	SV-87613r2_rule		Medium

Description
For completeness of forensic analysis, it is necessary to track who logs on to PostgreSQL. Concurrent connections by the same user from multiple workstations may be valid use of the system; or such connections may be due to improper circumvention of the requirement to use the CAC for authentication; or they may indicate unauthorized account sharing; or they may be because an account has been compromised. (If the fact of multiple, concurrent logons by a given user can be reliably reconstructed from the log entries for other events (logons/connections; voluntary and involuntary disconnections), then it is not mandatory to create additional log entries specifically for this.)

Description

For completeness of forensic analysis, it is necessary to track who logs on to PostgreSQL. Concurrent connections by the same user from multiple workstations may be valid use of the system; or such connections may be due to improper circumvention of the requirement to use the CAC for authentication; or they may indicate unauthorized account sharing; or they may be because an account has been compromised. (If the fact of multiple, concurrent logons by a given user can be reliably reconstructed from the log entries for other events (logons/connections; voluntary and involuntary disconnections), then it is not mandatory to create additional log entries specifically for this.)

STIG	Date
PostgreSQL 9.x Security Technical Implementation Guide	2018-09-19

Details

Check Text ( C-73091r1_chk )
First, as the database administrator, verify that log_connections and log_disconnections are enabled by running the following SQL: $ sudo su - postgres $ psql -c "SHOW log_connections" $ psql -c "SHOW log_disconnections" If either is off, this is a finding. Next, verify that log_line_prefix contains sufficient information by running the following SQL: $ sudo su - postgres $ psql -c "SHOW log_line_prefix" If log_line_prefix does not contain at least %m %u %d %c, this is a finding.

Check Text ( C-73091r1_chk )

First, as the database administrator, verify that log_connections and log_disconnections are enabled by running the following SQL:

$ sudo su - postgres
$ psql -c "SHOW log_connections"
$ psql -c "SHOW log_disconnections"

If either is off, this is a finding.

Next, verify that log_line_prefix contains sufficient information by running the following SQL:

$ sudo su - postgres
$ psql -c "SHOW log_line_prefix"

If log_line_prefix does not contain at least %m %u %d %c, this is a finding.

Fix Text (F-79407r2_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. First, as the database administrator (shown here as "postgres"), edit postgresql.conf: $ sudo su - postgres $ vi ${PGDATA?}/postgresql.conf Edit the following parameters as such: log_connections = on log_disconnections = on log_line_prefix = '< %m %u %d %c: >' Where: * %m is the time and date * %u is the username * %d is the database * %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-79407r2_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.

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

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

Edit the following parameters as such:

log_connections = on
log_disconnections = on
log_line_prefix = '< %m %u %d %c: >'

Where:
* %m is the time and date
* %u is the username
* %d is the database
* %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