AlmaLinux OS 9 must define default permissions for PAM users.

Overview

Finding IDVersionRule IDIA ControlsSeverity
V-269236ALMA-09-017730SV-269236r1050118_ruleCCI-000366medium
Description
Setting the most restrictive default permissions ensures that when new accounts are created they do not have unnecessary access. With a UMASK of 077, files will be created with 0600 permissions (owner read/write only) and directories will have 0700 permissions (owner read/write/execute only).
STIGDate
CloudLinux AlmaLinux OS 9 Security Technical Implementation Guide2025-05-22

Details

Check Text (C-269236r1050118_chk)

Verify that the "pam_umask" module is enabled with the following command: $ grep -i umask /etc/pam.d/* /etc/pam.d/postlogin:session optional pam_umask.so silent umask=0022 If a "pam_umask.so" line is not returned, this is a finding. If the "umask" setting is set to anything other than "0077", this is a finding. Note: If the "umask" setting is not found, it will use the default UMASK entry in /etc/login.defs.

Fix Text (F-73168r1049353_fix)

Configure AlmaLinux OS 9 to define default permissions for all authenticated users so the user can only read and modify their own files. Add or edit the following line at the top of /etc/pam.d/postlogin: session optional pam_umask.so silent