Successful/unsuccessful uses of the su command must generate an audit record.

Overview

Finding ID	Version	Rule ID	IA Controls	Severity
V-75691	UBTU-16-020360	SV-90371r3_rule		Medium

Description
Without establishing what type of events occurred, it would be difficult to establish, correlate, and investigate the events leading up to an outage or attack. Audit record content that may be necessary to satisfy this requirement includes, for example, time stamps, source and destination addresses, user/process identifiers, event descriptions, success/fail indications, filenames involved, and access control or flow control rules invoked. Associating event types with detected events in the Ubuntu operating system audit logs provides a means of investigating an attack; recognizing resource utilization or capacity thresholds; or identifying an improperly configured Ubuntu operating system. Satisfies: SRG-OS-000037-GPOS-00015, SRG-OS-000042-GPOS-00020, SRG-OS-000062-GPOS-00031, SRG-OS-000064-GPOS-0003, SRG-OS-000392-GPOS-00172, SRG-OS-000462-GPOS-00206, SRG-OS-000471-GPOS-00215

Description

Without establishing what type of events occurred, it would be difficult to establish, correlate, and investigate the events leading up to an outage or attack. Audit record content that may be necessary to satisfy this requirement includes, for example, time stamps, source and destination addresses, user/process identifiers, event descriptions, success/fail indications, filenames involved, and access control or flow control rules invoked. Associating event types with detected events in the Ubuntu operating system audit logs provides a means of investigating an attack; recognizing resource utilization or capacity thresholds; or identifying an improperly configured Ubuntu operating system. Satisfies: SRG-OS-000037-GPOS-00015, SRG-OS-000042-GPOS-00020, SRG-OS-000062-GPOS-00031, SRG-OS-000064-GPOS-0003, SRG-OS-000392-GPOS-00172, SRG-OS-000462-GPOS-00206, SRG-OS-000471-GPOS-00215

STIG	Date
Canonical Ubuntu 16.04 LTS Security Technical Implementation Guide	2018-07-18

Details

Check Text ( C-75377r2_chk )
Verify the Ubuntu operating system generates audit records when successful/unsuccessful attempts to use the "su" command occur. Check for the following system call being audited by performing the following command to check the file system rules in "/etc/audit/audit.rules": # sudo grep -iw /bin/su /etc/audit/audit.rules -a always,exit -F path=/bin/su -F perm=x -F auid>=1000 -F auid!=4294967295 -k privileged-priv_change If the command does not return a line, or the line is commented out, this is a finding.

Check Text ( C-75377r2_chk )

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

Check for the following system call being audited by performing the following command to check the file system rules in "/etc/audit/audit.rules":

# sudo grep -iw /bin/su /etc/audit/audit.rules

-a always,exit -F path=/bin/su -F perm=x -F auid>=1000 -F auid!=4294967295 -k privileged-priv_change

If the command does not return a line, or the line is commented out, this is a finding.

Fix Text (F-82319r2_fix)
Configure the Ubuntu operating system to generate audit records when successful/unsuccessful attempts to use the "su" command occur. Add or update the following rule in "/etc/audit/audit.rules": -a always,exit -F path=/bin/su -F perm=x -F auid>=1000 -F auid!=4294967295 -k privileged-priv_change The audit daemon must be restarted for the changes to take effect. To restart the audit daemon, run the following command: # sudo systemctl restart auditd.service

Fix Text (F-82319r2_fix)

Configure the Ubuntu operating system to generate audit records when successful/unsuccessful attempts to use the "su" command occur.

Add or update the following rule in "/etc/audit/audit.rules":

-a always,exit -F path=/bin/su -F perm=x -F auid>=1000 -F auid!=4294967295 -k privileged-priv_change

The audit daemon must be restarted for the changes to take effect. To restart the audit daemon, run the following command:

# sudo systemctl restart auditd.service