RHEL 10 must define default permissions for the c shell.

STIG ID: RHEL-10-400320  |  SRG: SRG-OS-000080-GPOS-00048 |  Severity: medium (CAT II)  |  CCI: CCI-000213 |  Vulnerability Id: V-281081

Vulnerability Discussion

The "umask" controls the default access mode assigned to newly created files. A "umask" of "077" limits new files to mode "600" or less permissive. Although "umask" can be represented as a four-digit number, the first digit representing special access modes is typically ignored or required to be "0".

This requirement applies to the globally configured system defaults and the local interactive user defaults for each account on the system.

Check

Verify the RHEL 10 "umask" setting is configured correctly in the "/etc/csh.cshrc" file with the following command:

Note: If the value of the "umask" parameter is set to "000" in the "/etc/csh.cshrc" file, the Severity is raised to a CAT I.

$ sudo grep umask /etc/csh.cshrc
umask 077

If the value for the "umask" parameter is not "077", or the "umask" parameter is missing or is commented out, this is a finding.

Fix

Configure RHEL 10 to define default permissions for all authenticated users using the c shell.

Add or edit the lines for the "umask" parameter in the "/etc/csh.cshrc" file to "077":

umask 077