Try it using Invoke-Atomic

Scheduled Task/Job: Systemd Timers

Description from ATT&CK

Adversaries may abuse systemd timers to perform task scheduling for initial or recurring execution of malicious code. Systemd timers are unit files with file extension <code>.timer</code> that control services. Timers can be set to run on a calendar event or after a time span relative to a starting point. They can be used as an alternative to Cron in Linux environments.(Citation: archlinux Systemd Timers Aug 2020) Systemd timers may be activated remotely via the <code>systemctl</code> command line utility, which operates over SSH.(Citation: Systemd Remote Control)

Each <code>.timer</code> file must have a corresponding <code>.service</code> file with the same name, e.g., <code>example.timer</code> and <code>example.service</code>. <code>.service</code> files are Systemd Service unit files that are managed by the systemd system and service manager.(Citation: Linux man-pages: systemd January 2014) Privileged timers are written to <code>/etc/systemd/system/</code> and <code>/usr/lib/systemd/system</code> while user level are written to <code>~/.config/systemd/user/</code>.

An adversary may use systemd timers to execute malicious code at system startup or on a scheduled basis for persistence.(Citation: Arch Linux Package Systemd Compromise BleepingComputer 10JUL2018)(Citation: gist Arch package compromise 10JUL2018)(Citation: acroread package compromised Arch Linux Mail 8JUL2018) Timers installed using privileged paths may be used to maintain root level persistence. Adversaries may also install user level timers to achieve user level persistence. https://www.aleksandrhovhannisyan.com/blog/how-to-add-a-copy-to-clipboard-button-to-your-jekyll-blog/

Atomic Tests

Atomic Test #1 - Create Systemd Service and Timer

This test creates Systemd service and timer then starts and enables the Systemd timer

Supported Platforms: linux

auto_generated_guid: f4983098-bb13-44fb-9b2c-46149961807b

Inputs:

Name Description Type Default Value
path_to_systemd_service Path to systemd service unit file Path /etc/systemd/system/art-timer.service
path_to_systemd_timer Path to service timer file Path /etc/systemd/system/art-timer.timer
systemd_service_name Name of systemd service String art-timer.service
systemd_timer_name Name of systemd service timer String art-timer.timer

Attack Commands: Run with bash!

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echo "[Unit]" > #{path_to_systemd_service}
echo "Description=Atomic Red Team Systemd Timer Service" >> #{path_to_systemd_service}
echo "[Service]" >> #{path_to_systemd_service}
echo "Type=simple" >> #{path_to_systemd_service}
echo "ExecStart=/bin/touch /tmp/art-systemd-timer-marker" >> #{path_to_systemd_service}
echo "[Install]" >> #{path_to_systemd_service}
echo "WantedBy=multi-user.target" >> #{path_to_systemd_service}
echo "[Unit]" > #{path_to_systemd_timer}
echo "Description=Executes Atomic Red Team Systemd Timer Service" >> #{path_to_systemd_timer}
echo "Requires=#{systemd_service_name}" >> #{path_to_systemd_timer}
echo "[Timer]" >> #{path_to_systemd_timer}
echo "Unit=#{systemd_service_name}" >> #{path_to_systemd_timer}
echo "OnCalendar=*-*-* *:*:00" >> #{path_to_systemd_timer}
echo "[Install]" >> #{path_to_systemd_timer}
echo "WantedBy=timers.target" >> #{path_to_systemd_timer}
systemctl start #{systemd_timer_name}
systemctl enable #{systemd_timer_name}
systemctl daemon-reload

Cleanup Commands:

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systemctl stop #{systemd_timer_name}
systemctl disable #{systemd_timer_name}
rm #{path_to_systemd_service}
rm #{path_to_systemd_timer}
systemctl daemon-reload

Atomic Test #2 - Create a user level transient systemd service and timer

Schedule a user level transient task (will not survive a reboot) without having to create the .timer or .service files by using the systemd-run command.

Supported Platforms: linux

auto_generated_guid: 3de33f5b-62e5-4e63-a2a0-6fd8808c80ec

Inputs:

None

Attack Commands: Run with sh!

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systemd-run --user --unit=Atomic-Red-Team --on-calendar '*:0/1' /bin/sh -c 'echo "$(date) $(whoami)" >>/tmp/log'

Cleanup Commands:

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systemctl --user stop Atomic-Red-Team.service
systemctl --user stop Atomic-Red-Team.timer
rm /tmp/log

Dependencies: Run with sh!

Description: Check if systemd-run exists on the machine

Check Prereq Commands:

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if [ -x "$(command -v systemd-run)" ]; then exit 0; else exit 1; fi;

Get Prereq Commands:

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echo "Install systemd on the machine."; exit 1;

Atomic Test #3 - Create a system level transient systemd service and timer

Schedule a system level transient task (will not survive a reboot) without having to create the .timer or .service files by using the systemd-run command.

Supported Platforms: linux

auto_generated_guid: d3eda496-1fc0-49e9-aff5-3bec5da9fa22

Inputs:

None

Attack Commands: Run with sh! Elevation Required (e.g. root or admin)

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systemd-run --unit=Atomic-Red-Team --on-calendar '*:0/1' /bin/sh -c 'echo "$(date) $(whoami)" >>/tmp/log'

Cleanup Commands:

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systemctl stop Atomic-Red-Team.service
systemctl stop Atomic-Red-Team.timer
rm /tmp/log

Dependencies: Run with sh!

Description: Check if systemd-run exists on the machine

Check Prereq Commands:

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if [ -x "$(command -v systemd-run)" ]; then exit 0; else exit 1; fi;

Get Prereq Commands:

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echo "Install systemd on the machine."; exit 1;

source