The aliases file must be group-owned by root, sys, bin, or system.
Overview
| Finding ID | Version | Rule ID | IA Controls | Severity |
|---|---|---|---|---|
| V-22438 | GEN004370 | SV-37473r2_rule | Medium |
| Description |
|---|
| If the alias file is not group-owned by root or a system group, an unauthorized user may modify the file adding aliases to run malicious code or redirect e-mail. |
| STIG | Date |
|---|---|
| Red Hat Enterprise Linux 5 Security Technical Implementation Guide | 2017-03-01 |
Details
| Check Text ( C-36139r2_chk ) |
|---|
| If the "sendmail" and "postfix" packages are not installed, this is not applicable. Check the group ownership of the alias files. Procedure: for sendmail: # ls -lL /etc/aliases If the files are not group-owned by root, this is a finding. # ls -lL /etc/aliases.db If the file is not group-owned by the same system group as sendmail, which is smmsp by default, this is a finding. for postfix: Verify the location of the alias file. # postconf alias maps This will return the location of the "aliases" file, by default "/etc/postfix/aliases" # ls -lL If the files are not group-owned by root, this is a finding. # ls -lL If the file is not group-owned by root, this is a finding. |
| Fix Text (F-31385r1_fix) |
|---|
| Change the group-owner of the /etc/aliases file. Procedure: for sendmail: # chgrp root /etc/aliases # chgrp smmsp /etc/aliases.db The aliases.db file must be owned by the same system group as sendmail, which is smmsp by default. for postfix # chgrp root /etc/postfix/aliases # chgrp root /etc/postfix/aliases.db |