Security Audit of Office Printers: What Your IT Team Should Watch For
In today’s connected office environments, printers are no longer just passive output devices. They often reside on the network, store sensitive data, and sometimes even function as a backdoor into corporate systems. A comprehensive security audit of office printers is therefore not optional-it’s essential. Below are key areas your IT team should review to safeguard your print infrastructure.
1. Firmware and Software Updates
Printers are essentially specialized computers; they run firmware and sometimes embedded operating systems. If left unpatched, they can become vulnerable to exploits—just like PCs. During your audit:
– Check the current firmware version on each printer against the vendor’s latest release.
– Verify that automatic update or alerting mechanisms are enabled (where supported).
– Document printers that no longer receive vendor updates (end‑of‑life) and plan for their replacement.
2. Network Segmentation and Access Controls
One of the most overlooked risks is allowing printers and other peripherals to exist on the same flat network as sensitive systems. To mitigate:
– Ensure printers are placed in a dedicated subnet or VLAN with restricted access.
– Enable firewall rules or ACLs (Access Control Lists) to limit which devices can communicate with the printer.
– Use strong authentication for administrative interfaces (e.g., unique passwords, change default credentials).
3. Data Storage and Remanence
Many modern multifunction printers (MFPs) store scanned documents, job logs, or even full‑page images temporarily (or longer). This creates a data retention risk. Audit steps include:
– Review the printer’s internal storage: what data is kept, for how long, and where it resides.
– If a printer is being decommissioned, confirm secure erasure of its storage media—whether a hard drive or flash memory.
– Check for encryption support: Are stored job logs or cached pages encrypted at rest and in transit?
4. Print Job Confidentiality
Sensitive documents printed to shared printers may inadvertently display on the output tray or be picked up by the wrong person. To improve confidentiality:
– Enable a “secure release” or “follow‑me printing” feature: jobs hold on the printer until the user authenticates.
– Review and, if necessary, adjust default settings so printed jobs are not stored in indefinite “spooled” states.
– Educate users: walk away only after retrieving their printouts; avoid leaving documents unattended.
5. Monitoring and Logging
Printers are often an afterthought for monitoring, but they can provide valuable forensic data. During your audit:
– Confirm that the printer’s event logs (login attempts, scanned jobs, admin changes) are being forwarded to your centralized logging or SIEM system.
– Check for alerts on unusual behavior (e.g., many failed login attempts, unusual job sizes or destinations).
– Periodically review logs for unapproved changes to configuration or firmware.
6. Physical Security and Disposal
While logical security is vital, physical access to a printer’s control panel or hard drive must not be ignored:
– Ensure the device is located in a secure area, ideally locked or guarded if it handles sensitive output.
– When replacing or disposing of a printer, follow a formal disposal procedure that includes wiping or physically destroying internal media.
– Maintain inventory records of printer locations, serial numbers, and disposal dates for audit purposes.
7. Vendor and Third‑Party Software Risks
Printers often integrate with additional tools: scanning feeds, cloud print services, mobile print apps, even IoT device management. These integrations can widen your risk surface:
– Evaluate any third‑party software or cloud services associated with your printers for security best practices.
– Confirm that service credentials are unique and limited in privileges.
– Require vendors to provide documentation on how they secure data in transit, at rest, and how they patch their software.
8. Policy, Awareness and Incident Preparedness
Finally, technical controls must be complemented with process and people controls:
– Define and document a “Printer Security Policy” that covers everything from user access to scheduled audits and disposal.
– Train staff and users on secure printing practices—such as using PIN release, selecting correct output trays, and promptly retrieving documents.
– Include printers in your incident response playbook: know who is responsible if a printer is compromised or logs show suspicious activity.
Conclusion
Printers may appear innocuous, but in modern enterprise networks they can become significant security liabilities. By conducting a thorough audit focused on firmware management, network segmentation, data retention, job confidentiality, monitoring, physical security, vendor integration, and user policy, your IT team can dramatically reduce risk. Prioritize printers in your next security review—because attackers may see them as low‑hanging fruit.
