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Service Recovery After Compromise

MediumDigital Forensics & Incident Response20-30 min
The brief

During the incident, the attacker sabotaged a legitimate service two ways: they dropped a malicious systemd override that replaces its ExecStart with their own payload, and they disabled the service so the clean version wouldn't start on boot. The service name is in /root/case/assignment.env (SERVICE). Recover it: remove the malicious drop-in override so the unit runs its real ExecStart again, and re-enable the service so it starts at boot. Grading reads the systemd config on disk.

What you'll do
  • Find and remove the malicious drop-in override
  • Re-enable the service (recreate its boot enable symlink)
  • Leave the legitimate unit intact

Hands-on lab: you work on a real Linux box in your browser, graded on the machine's actual state.