OL 8 must be configured to prevent unrestricted mail relaying.
An XCCDF Rule
Description
<VulnDiscussion>If unrestricted mail relaying is permitted, unauthorized senders could use this host as a mail relay to send spam or for other unauthorized activity.</VulnDiscussion><FalsePositives></FalsePositives><FalseNegatives></FalseNegatives><Documentable>false</Documentable><Mitigations></Mitigations><SeverityOverrideGuidance></SeverityOverrideGuidance><PotentialImpacts></PotentialImpacts><ThirdPartyTools></ThirdPartyTools><MitigationControl></MitigationControl><Responsibility></Responsibility><IAControls></IAControls>
- ID
- SV-248895r780251_rule
- Severity
- Medium
- References
- Updated
Remediation - 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:
$ sudo postconf -e 'smtpd_client_restrictions = permit_mynetworks,reject'