The alias file must not have an extended ACL.

Overview

Finding ID	Version	Rule ID	IA Controls	Severity
V-22439	GEN004390	SV-26687r1_rule	ECLP-1	Medium

Description
Excessive permissions on the aliases file may permit unauthorized modification. If the alias file is modified by an unauthorized user, they may modify the file to run malicious code or redirect email.

STIG	Date
SOLARIS 10 SPARC SECURITY TECHNICAL IMPLEMENTATION GUIDE	2016-06-22

Details

Check Text ( C-39386r1_chk )
Find the alias files on the system. Procedure: # egrep '^O(A\| AliasFile)' /etc/mail/sendmail.cf If the "alias file" is an NIS or LDAP map, this check is not applicable. The default location is /etc/mail/aliases. Check the permissions of the alias file and the hashed version of it used by sendmail. Procedure: # ls -lL /etc/mail/aliases /etc/mail/aliases.db If the permissions include a "+", the file has an extended ACL and this is a finding.

Check Text ( C-39386r1_chk )

Find the alias files on the system.

Procedure:
# egrep '^O(A| AliasFile)' /etc/mail/sendmail.cf

If the "alias file" is an NIS or LDAP map, this check is not applicable. The default location is /etc/mail/aliases.

Check the permissions of the alias file and the hashed version of it used by sendmail.

Procedure:
# ls -lL /etc/mail/aliases /etc/mail/aliases.db

If the permissions include a "+", the file has an extended ACL and this is a finding.

Fix Text (F-23928r1_fix)
Remove the extended ACL from the files. # chmod A- /etc/mail/aliases /etc/mail/aliases.db