AlmaLinux OS 9 must have the postfix package installed.

Severity	Group ID	Group Title	Version	Rule ID	Date	STIG Version
medium	V-272485	SRG-OS-000304-GPOS-00121	ALMA-09-006845	SV-272485r1069405_rule	2025-02-20	1

Description
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 like 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

Description

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 like 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

ℹ️ Check
Verify that AlmaLinux OS 9 has the postfix package installed with the following command: $ dnf list --installed postfix Example output: postfix.x86_64 2:3.5.9-24.el9 @AppStream If the "postfix" package is not installed, this is a finding.

✔️ Fix
Install the postfix package with the following command: $ sudo dnf install postfix