cis-ubuntu1604-v200-4-1-7

DevOps & Security

Ensure login and logout events are collected

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Source SKILL.md: https://github.com/CyberStrikeus/CyberStrike/blob/HEAD/.cyberstrike/skill/CIS_benchmarks/Operating_Systems/Ubuntu/CIS_Ubuntu_Linux_16.04_LTS_Benchmark_v2.0.0/cis-ubuntu1604-v200-4-1-7/SKILL.md

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CIS Ubuntu Linux 16.04 LTS Benchmark v2.0.0 - Control 4.1.7

Profile

Level: 2 - Server
Level: 2 - Workstation
Assessment Status: Automated

Description

Monitor login and logout events. The parameters below track changes to files associated with login/logout events. The file /var/log/faillog tracks failed events from login. The file /var/log/lastlog maintain records of the last time a user successfully logged in. The file /var/log/tallylog maintains records of failures via the pam_tally2 module.

Note: Reloading the auditd config to set active settings requires the auditd service to be restarted, and may require a system reboot.

Rationale

Monitoring login/logout events could provide a system administrator with information associated with brute force attacks against user logins.

Impact

None.

Audit Procedure

Command Line

Run the following command to verify the rules are contained in a .rules file in the /etc/audit/rules.d/ directory:

grep logins /etc/audit/rules.d/*.rules

Verify output includes:

-w /var/log/faillog -p wa -k logins
-w /var/log/lastlog -p wa -k logins
-w /var/log/tallylog -p wa -k logins

Run the following command to verify that rules are in the running auditd config:

auditctl -l | grep logins

Verify output includes:

-w /var/log/faillog -p wa -k logins
-w /var/log/lastlog -p wa -k logins
-w /var/log/tallylog -p wa -k logins

Expected Result

Output should include the rules listed above.

Remediation

Command Line

Edit or create a file in the /etc/audit/rules.d/ directory ending in .rules.

Example: vi /etc/audit/rules.d/50-logins.rules

Add the following lines:

-w /var/log/faillog -p wa -k logins
-w /var/log/lastlog -p wa -k logins
-w /var/log/tallylog -p wa -k logins

Default Value

By default, no audit rules are configured for login/logout events.

References

CIS Ubuntu Linux 16.04 LTS Benchmark v2.0.0 - Section 4.1.7

CIS Controls

Controls Version	Control
v7	4.9 Log and Alert on Unsuccessful Administrative Account Login - Configure systems to issue a log entry and alert on unsuccessful logins to an administrative account.
v7	16.11 Lock Workstation Sessions After Inactivity - Automatically lock workstation sessions after a standard period of inactivity.
v7	16.13 Alert on Account Login Behavior Deviation - Alert when users deviate from normal login behavior, such as time-of-day, workstation location and duration.