IT Forensics · Linux
Forensic analysis of systemd timers – Evaluating a modern alternative to traditional cron
systemd timers offer an alternative to Cron for running tasks on a schedule and are closely linked to systemd service units. They are increasingly being used in place of traditional Cron configurations on modern distributions.
As timer units always control an associated service unit, a comprehensive forensic assessment requires both configuration files to be examined together.
Why LanCologne?
Since its foundation, LanCologne has specialised in professional IT forensics. Our staff have decades of experience in the field of information technology and assist companies, solicitors, private individuals and, on a regular basis, the courts in the technical investigation of complex digital matters.
The examination is, as a matter of principle, carried out exclusively on a forensic copy, a forensic image or a data source captured in a technically equivalent manner that preserves the integrity of the evidence. The original evidence remains unchanged and is stored in a manner that preserves its integrity.
Our services
We record all existing systemd timers and their associated service units, check their execution schedules, and map any unusual combinations to the referenced executable files.
Typical areas of application
This is how a systemd timer analysis works
Once the backup has been completed, all timer units are recorded and reconciled with their respective service units. Execution plans and referenced executable files are documented and checked for plausibility against known standard configurations for the relevant distribution.
Why is timer analysis relevant in a forensic context?
As modern distributions are increasingly using systemd timers instead of Cron, this configuration source must be examined just as systematically as traditional Cron when searching for time-controlled persistence mechanisms.
Looking at the timer or the service unit in isolation may lead to relevant interrelationships being overlooked, which is why both are always analysed together.
Frequently Asked Questions
LanCologne – Linux Forensics Cologne
Do you require a professional forensic investigation into „forensic analysis of Systemd timers"? LanCologne can assist you with the legally admissible preservation of digital evidence and the transparent analysis of relevant Linux artefacts.
Related to this topic
- Forensic analysis of init.d scripts – Checking traditional system boot mechanisms
- Forensic identification of autostart mechanisms in Linux – An overview of all relevant persistence methods
- Forensic analysis of udev rules – examining device management as a source of persistence
- Forensic analysis of kernel modules – checking extensions to kernel functionality