The Oracle Linux operating system must be configured to prevent unrestricted mail relaying.
An XCCDF Rule
Description
If unrestricted mail relaying is permitted, unauthorized senders could use this host as a mail relay for the purpose of sending spam or other unauthorized activity.
- ID
- SV-221883r991589_rule
- Version
- OL07-00-040680
- Severity
- Medium
- References
- Updated
Remediation Templates
A Manual Procedure
If "postfix" is installed, modify the "/etc/postfix/main.cf" file to restrict client connections to the local network with the following command:
# postconf -e 'smtpd_client_restrictions = permit_mynetworks,reject'