PGS9-00-010200 - PostgreSQL must enforce authorized access to all PKI private keys stored/utilized by PostgreSQL.

Information

The DoD standard for authentication is DoD-approved PKI certificates. PKI certificate-based authentication is performed by requiring the certificate holder to cryptographically prove possession of the corresponding private key.

If the private key is stolen, an attacker can use the private key(s) to impersonate the certificate holder. In cases where PostgreSQL-stored private keys are used to authenticate PostgreSQL to the system's clients, loss of the corresponding private keys would allow an attacker to successfully perform undetected man-in-the-middle attacks against PostgreSQL system and its clients.

Both the holder of a digital certificate and the issuing authority must take careful measures to protect the corresponding private key. Private keys should always be generated and protected in FIPS 140-2 or 140-3 validated cryptographic modules.

All access to the private key(s) of PostgreSQL must be restricted to authorized and authenticated users. If unauthorized users have access to one or more of PostgreSQL's private keys, an attacker could gain access to the key(s) and use them to impersonate the database on the network or otherwise perform unauthorized actions.

Solution

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.

Store all PostgreSQL PKI private keys in a FIPS 140-2 or 140-3 validated cryptographic module.

Ensure access to PostgreSQL PKI private keys is restricted to only authenticated and authorized users.

PostgreSQL private key(s) can be stored in $PGDATA directory, which is only accessible by the database owner (usually postgres, DBA) user. Do not allow access to this system account to unauthorized users.

To put the keys in a different directory, as the database administrator (shown here as 'postgres'), set the following settings to a protected directory:

$ sudo su - postgres
$ vi ${PGDATA?}/postgresql.conf
ssl_ca_file = '/some/protected/directory/root.crt'
ssl_crl_file = '/some/protected/directory/root.crl'
ssl_cert_file = '/some/protected/directory/server.crt'
ssl_key_file = '/some/protected/directory/server.key'

Now, as the system administrator, restart the server with the new configuration:

# SYSTEMD SERVER ONLY
$ sudo systemctl restart postgresql-${PGVER?}

# INITD SERVER ONLY
$ sudo service postgresql-${PGVER?} restart

For more information on configuring PostgreSQL to use SSL, see supplementary content APPENDIX-G.

Item Details

Audit Name: DISA STIG PostgreSQL 9.x on RHEL OS v2r5

Category: IDENTIFICATION AND AUTHENTICATION

Plugin: Unix

Control ID: 7982208f7d1d0f78901576451821c1e98885ba9dccdd160ce1634519894bb95d

Detections

Analytics

PGS9-00-010200 - PostgreSQL must enforce authorized access to all PKI private keys stored/utilized by PostgreSQL.

Information

Solution

See Also

Item Details