The Red Hat Enterprise Linux operating system must audit all uses of the umount command.

Overview

Finding ID	Version	Rule ID	IA Controls	Severity
V-72173	RHEL-07-030750	SV-86797r6_rule		Medium

Description
Reconstruction of harmful events or forensic analysis is not possible if audit records do not contain enough information. At a minimum, the organization must audit the full-text recording of privileged mount commands. The organization must maintain audit trails in sufficient detail to reconstruct events to determine the cause and impact of compromise. When a user logs on, the auid is set to the uid of the account that is being authenticated. Daemons are not user sessions and have the loginuid set to -1. The auid representation is an unsigned 32-bit integer, which equals 4294967295. The audit system interprets -1, 4294967295, and "unset" in the same way. Satisfies: SRG-OS-000042-GPOS-00020, SRG-OS-000392-GPOS-00172

Description

Reconstruction of harmful events or forensic analysis is not possible if audit records do not contain enough information. At a minimum, the organization must audit the full-text recording of privileged mount commands. The organization must maintain audit trails in sufficient detail to reconstruct events to determine the cause and impact of compromise. When a user logs on, the auid is set to the uid of the account that is being authenticated. Daemons are not user sessions and have the loginuid set to -1. The auid representation is an unsigned 32-bit integer, which equals 4294967295. The audit system interprets -1, 4294967295, and "unset" in the same way. Satisfies: SRG-OS-000042-GPOS-00020, SRG-OS-000392-GPOS-00172

STIG	Date
Red Hat Enterprise Linux 7 Security Technical Implementation Guide	2020-05-15

Details

Check Text ( C-72407r7_chk )
Verify the operating system generates audit records when successful/unsuccessful attempts to use the "umount" command occur. Check that the following system call is being audited by performing the following series of commands to check the file system rules in "/etc/audit/audit.rules": # grep -iw "/usr/bin/umount" /etc/audit/audit.rules -a always,exit -F path=/usr/bin/umount -F auid>=1000 -F auid!=unset -k privileged-mount If the command does not return any output, this is a finding.

Check Text ( C-72407r7_chk )

Verify the operating system generates audit records when successful/unsuccessful attempts to use the "umount" command occur.

Check that the following system call is being audited by performing the following series of commands to check the file system rules in "/etc/audit/audit.rules":

# grep -iw "/usr/bin/umount" /etc/audit/audit.rules

-a always,exit -F path=/usr/bin/umount -F auid>=1000 -F auid!=unset -k privileged-mount

If the command does not return any output, this is a finding.

Fix Text (F-78527r6_fix)
Configure the operating system to generate audit records when successful/unsuccessful attempts to use the "umount" command occur. Add or update the following rule in "/etc/audit/rules.d/audit.rules": -a always,exit -F path=/usr/bin/umount -F auid>=1000 -F auid!=unset -k privileged-mount The audit daemon must be restarted for the changes to take effect.