The file integrity tool must be configured to verify extended attributes.

Overview

Finding ID	Version	Rule ID	IA Controls	Severity
V-75521	UBTU-16-010530	SV-90201r1_rule		Low

Description
Extended attributes in file systems are used to contain arbitrary data and file metadata with security implications.

STIG	Date
Canonical Ubuntu 16.04 Security Technical Implementation Guide	2020-05-29

Details

Check Text ( C-75225r1_chk )
Verify the file integrity tool is configured to verify extended attributes. Check to see if Advanced Intrusion Detection Environment (AIDE) is installed with the following command: # dpkg -l \|grep aide ii aide 0.16~a2.git20130520-3 ii aide-common 0.16~a2.git20130520-3 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 with the following command: # egrep "[+]?xattrs" /etc/aide/aide.conf VarFile = OwnerMode+n+l+X+xattrs If the "xattrs" 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-75225r1_chk )

Verify the file integrity tool is configured to verify extended attributes.

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

# dpkg -l |grep aide

ii aide 0.16~a2.git20130520-3
ii aide-common 0.16~a2.git20130520-3

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 with the following command:

# egrep "[+]?xattrs" /etc/aide/aide.conf

VarFile = OwnerMode+n+l+X+xattrs

If the "xattrs" 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-82149r1_fix)
Configure the file integrity tool to check file and directory extended attributes. If AIDE is installed, ensure the "xattrs" rule is present on all file and directory selection lists.