RHEL-09-215101 RHEL 9 must have the Postfix package installed.
All changes in this version
Maps to AC-2(1) via CCI-000015
Title
RHEL 9 must have the Postfix package installed.
Control
Note: If the admin can demonstrate that there is another system/service to send audit failure notifications to the administrator/ISSO, this control is not applicable. Verify RHEL 9 has the Postfix package installed with the following command: $ sudo dnf list --installed postfix Example output: postfix.x86_64 2:3.5.25-1.el9 If the "postfix" package is not installed, this is a finding.
Discussion
Postfix is a free, open-source mail transfer agent (MTA) that sends and receives emails. It is a server-side application that can be used to set up a local mail server, create a null-client mail relay, use a Postfix server as a destination for multiple domains, or choose an LDAP directory instead of files for lookups. Postfix supports protocols such as LDAP, SMTP AUTH (SASL), and TLS. It uses the Simple Mail Transfer Protocol (SMTP) to transfer emails between servers. Satisfies: SRG-OS-000304-GPOS-00121, SRG-OS-000343-GPOS-00134, SRG-OS-000363-GPOS-00150, SRG-OS-000447-GPOS-00201
Related controls
CCI-000015
Fix
Install the Postfix package with the following command: $ sudo dnf install postfix