All shell files must have mode 0755 or less permissive.

Overview

Finding ID	Version	Rule ID	IA Controls	Severity
V-922	GEN002220	SV-38846r1_rule	ECLP-1	High

Description
Shells with world/group write permissions give the ability to maliciously modify the shell to obtain unauthorized access.

STIG	Date
Draft AIX Security Technical Implementation Guide	2011-08-17

Details

Check Text ( C-37839r1_chk )
Obtain a list of system shells from /etc/security/login.cfg and check the permissions of these shells. Procedure: #grep shells /etc/security/login.cfg \| grep –v \* \| cut –f 2 –d = \| sed s/,/\ /g \| xargs –n1 ls –l If any shell has a mode more permissive than 0755, this is a finding. Obtain a list of system shells from /etc/shells and check the ownership of these shells. Procedure: #cat /etc/shells \| xargs –n1 ls -l If any shell has a mode more permissive than 0755, this is a finding.

Check Text ( C-37839r1_chk )

Obtain a list of system shells from /etc/security/login.cfg and check the permissions of these shells.
Procedure:
#grep shells /etc/security/login.cfg | grep –v \* | cut –f 2 –d = | sed s/,/\ /g | xargs –n1 ls –l
If any shell has a mode more permissive than 0755, this is a finding.

Obtain a list of system shells from /etc/shells and check the ownership of these shells.
Procedure:
#cat /etc/shells | xargs –n1 ls -l

If any shell has a mode more permissive than 0755, this is a finding.

Fix Text (F-33102r1_fix)
Change the mode of the shell. # chmod 0755 < shell >