RHEL 10 must be configured to prevent unrestricted mail relaying.
Overview
| Finding ID | Version | Rule ID | IA Controls | Severity |
| V-280999 | RHEL-10-200692 | SV-280999r1165352_rule | CCI-000381 | medium |
| Description | ||||
| If unrestricted mail relaying is permitted, unauthorized senders could use this host as a mail relay to send spam or for other unauthorized activity. | ||||
| STIG | Date | |||
| Red Hat Enterprise Linux 10 Security Technical Implementation Guide | 2026-03-11 | |||
Related Frameworks
3 paths across 3 frameworks
Related Frameworks
NIST 800-531 mapping
CM-7
1.00
- DISA · V1R1 · disa_xccdf · related
- DISA · 2025-01-23 · disa_cci_list · equivalent
NIST 800-1711 mapping
3.4.6
1.00
- DISA · V1R1 · disa_xccdf · related
- DISA · 2025-01-23 · disa_cci_list · equivalent
- NIST · Rev 2 (Feb 2020, errata Jan 2021) · nist_800_171_app_d · equivalent
CCI1 mapping
CCI-000381
1.00
- DISA · V1R1 · disa_xccdf · related
Details
Check Text (C-280999r1165352_chk)
Note: If postfix is not installed, this is not applicable.
Verify RHEL 10 is configured to prevent unrestricted mail relaying with the following command:
$ postconf -n smtpd_client_restrictions
smtpd_client_restrictions = permit_mynetworks,reject
If the "smtpd_client_restrictions" parameter contains any entries other than "permit_mynetworks" and "reject", and the additional entries have not been documented with the information system security officer, this is a finding.
Fix Text (F-85465r1165351_fix)
Configure RHEL 10 so that the postfix configuration file restricts client connections to the local network with the following command:
$ sudo postconf -e 'smtpd_client_restrictions = permit_mynetworks,reject'