Files executed through a mail aliases file must be owned by root and must reside within a directory owned and writable only by root.

Overview

Finding ID	Version	Rule ID	IA Controls	Severity
V-833	GEN004400	SV-37491r1_rule	ECLP-1	High

Description
If a file executed through a mail aliases file is not owned and writable only by root, it may be subject to unauthorized modification. Unauthorized modification of files executed through aliases may allow unauthorized users to attain root privileges.

STIG	Date
Red Hat Enterprise Linux 5 Security Technical Implementation Guide	2017-03-01

Details

Check Text ( C-36149r1_chk )
Verify the ownership of files referenced within the sendmail aliases file. Procedure: # more /etc/aliases Examine the aliases file for any utilized directories or paths. # ls -lL Check the owner for any paths referenced. Check if the file or parent directory is owned by root. If not, this is a finding.

Fix Text (F-31398r1_fix)
Edit the /etc/aliases file (alternatively, /usr/lib/sendmail.cf). Locate the entries executing a program. They will appear similar to the following line: Aliasname: : /usr/local/bin/ls (or some other program name) Ensure root owns the programs and the directory(ies) they reside in by using the chown command to change owner to root. Procedure: # chown root