The SUSE operating system file integrity tool must be configured to verify Access Control Lists (ACLs).

Overview

Finding ID	Version	Rule ID	IA Controls	Severity
V-77155	SLES-12-010520	SV-91851r1_rule		Low

Description
ACLs can provide permissions beyond those permitted through the file mode and must be verified by file integrity tools.

STIG	Date
SLES 12 Security Technical Implementation Guide	2018-09-27

Details

Check Text ( C-76765r1_chk )
Verify that the SUSE operating system file integrity tool is configured to verify extended attributes. Check to see if Advanced Intrusion Detection Environment (AIDE) is installed on the system with the following command: # sudo zypper if aide \| grep "Installed" Installed: Yes If AIDE is not installed, ask the System Administrator how file integrity checks are performed on the system. If there is no application installed to perform integrity checks, this is a finding. Note: AIDE is highly configurable at install time. These commands assume the "aide.conf" file is under the "/etc" directory. Use the following command to determine if the file is in another location: # find / -name aide.conf Check the "aide.conf" file to determine if the "xattrs" rule has been added to the rule list being applied to the files and directories selection lists. An example rule that includes the "acl" rule follows: All= p+i+n+u+g+s+m+S+sha512+acl+xattrs+selinux /bin All # apply the custom rule to the files in bin /sbin All # apply the same custom rule to the files in sbin If the "acl" rule is not being used on all selection lines in the "/etc/aide.conf" file, or extended attributes are not being checked by another file integrity tool, this is a finding.

Check Text ( C-76765r1_chk )

Verify that the SUSE operating system file integrity tool is configured to verify extended attributes.

Check to see if Advanced Intrusion Detection Environment (AIDE) is installed on the system with the following command:

# sudo zypper if aide | grep "Installed"

Installed: Yes

If AIDE is not installed, ask the System Administrator how file integrity checks are performed on the system.

If there is no application installed to perform integrity checks, this is a finding.

Note: AIDE is highly configurable at install time. These commands assume the "aide.conf" file is under the "/etc" directory.

Use the following command to determine if the file is in another location:

# find / -name aide.conf

Check the "aide.conf" file to determine if the "xattrs" rule has been added to the rule list being applied to the files and directories selection lists.

An example rule that includes the "acl" rule follows:

All= p+i+n+u+g+s+m+S+sha512+acl+xattrs+selinux
/bin All # apply the custom rule to the files in bin
/sbin All # apply the same custom rule to the files in sbin

If the "acl" rule is not being used on all selection lines in the "/etc/aide.conf" file, or extended attributes are not being checked by another file integrity tool, this is a finding.

Fix Text (F-83851r1_fix)
Configure the SUSE operating system file integrity tool to check file and directory ACLs. If AIDE is installed, ensure the "acl" rule is present on all file and directory selection lists.