Detections
Analytics

6.2.3.22 Ensure session initiation information is collected

Information

Monitor session initiation events. The parameters in this section track changes to the files associated with session events.

 - /var/run/utmp - tracks all currently logged in users.
 - /var/log/wtmp - file tracks logins, logouts, shutdown, and reboot events.
 - /var/log/btmp - keeps track of failed login attempts and can be read by entering the command /usr/bin/last -f /var/log/btmp.

All audit records will be tagged with the identifier "session."

Monitoring these files for changes could alert a system administrator to logins occurring at unusual hours, which could indicate intruder activity (i.e. a user logging in at a time when they do not normally log in).

Solution

- Add the audit rule(s) that monitor changes to /var/run/utmp, /var/log/wtmp, and /var/log/btmp . The procedure adds each rule only for targets that exist, so augenrules --load does not error. Run:

#!/usr/bin/env bash

{
 [ -e /var/run/utmp ] && printf '%s\n' "-a always,exit -S all -F path=/var/run/utmp -F perm=wa -F key=session"
 [ -e /var/log/wtmp ] && printf '%s\n' "-a always,exit -S all -F path=/var/log/wtmp -F perm=wa -F key=session"
 [ -e /var/log/btmp ] && printf '%s\n' "-a always,exit -S all -F path=/var/log/btmp -F perm=wa -F key=session"
} >> /etc/audit/rules.d/50-session.rules

 - Merge and load the rules into active configuration:

# augenrules --load

 - Check if reboot is required:

# if [[ $(auditctl -s | grep "enabled") =~ "2" ]]; then printf "Reboot required to load rules\n"; fi

See Also

https://workbench.cisecurity.org/benchmarks/27892

Item Details

Category: AUDIT AND ACCOUNTABILITY

References: 800-53|AU-3, 800-53|AU-3(1), 800-53|AU-7, 800-53|AU-12, CSCv7|4.9, CSCv7|16.13

Plugin: Unix

Control ID: 418b14c3572ec92a6bfcc8679c986d3994fa31328acfec1b33d7f968c7fddd1b