1.4.2 Ensure filesystem integrity is regularly checked

Information

Periodic checking of the filesystem integrity is needed to detect changes to the filesystem.

Notes:

The checking in this recommendation occurs every day at 5am. Alter the frequency and time of the checks in compliance with site policy

systemd timers, timer file aidecheck.timer and service file aidecheck.service, have been included as an optional alternative to using cron

Ubuntu advises using /usr/bin/aide.wrapper rather than calling /usr/bin/aide directly in order to protect the database and prevent conflicts

Rationale:

Periodic file checking allows the system administrator to determine on a regular basis if critical files have been changed in an unauthorized fashion.

Solution

If cron will be used to schedule and run aide check:
Run the following command:

# crontab -u root -e

Add the following line to the crontab:

0 5 * * * /usr/bin/aide.wrapper --config /etc/aide/aide.conf --check

OR
If aidecheck.service and aidecheck.timer will be used to schedule and run aide check:
Create or edit the file /etc/systemd/system/aidecheck.service and add the following lines:

[Unit]
Description=Aide Check

[Service]
Type=simple
ExecStart=/usr/bin/aide.wrapper --config /etc/aide/aide.conf --check

[Install]
WantedBy=multi-user.target

Create or edit the file /etc/systemd/system/aidecheck.timer and add the following lines:

[Unit]
Description=Aide check every day at 5AM

[Timer]
OnCalendar=*-*-* 05:00:00
Unit=aidecheck.service

[Install]
WantedBy=multi-user.target

Run the following commands:

# chown root:root /etc/systemd/system/aidecheck.*
# chmod 0644 /etc/systemd/system/aidecheck.*

# systemctl daemon-reload

# systemctl enable aidecheck.service
# systemctl --now enable aidecheck.timer

See Also

https://workbench.cisecurity.org/files/2920

Item Details

Category: AUDIT AND ACCOUNTABILITY

References: 800-53|AU-3, CSCv7|14.9

Plugin: Unix

Control ID: 6fd19cc697700aa29814e7a64f5527aa00e9b0e3574d2ccfb3a51301591d67c5