In a world where cloud security, AI-powered malware, and ransomware dominate discussions, there’s one class of devices that quietly escapes scrutiny printers.

They sit in corners, blinking, printing, scanning, and faxing. Despite looking harmless, many of them are full-fledged computers with embedded operating systems, open ports, remote access capabilities, and minimal security hardening. That combination makes them a surprisingly attractive and accessible attack vector.

Printers are no longer simple machines. They process confidential data, store documents, authenticate with cloud services, and integrate with internal networks. Yet they are often deployed with default settings, forgotten in patching cycles, and assumed to be low risk.

That assumption is wrong.

The Real Risks: Default Credentials, Exposed Panels, and Remote Interfaces

In many environments, printers ship with admin panels accessible via simple web interfaces. Worse, those interfaces are frequently left secured only by factory-set default credentials like admin/admin or root/1234.

It is not unusual to discover printers exposing:

• HTTP or HTTPS admin panels

• FTP and Telnet services

• SNMPv1 with public community strings

• LPD (Line Printer Daemon)

• VNC sessions offering full control of the interface

Some printers do not log access attempts. Others allow full control through a browser without any authentication or timeout. In certain cases, features like VNC are enabled silently, creating remote-access paths that no one in IT is even aware of.

These devices often reside inside trusted internal networks, where they become perfect footholds for lateral movement once an attacker gains access to any adjacent system.

Why Attackers Love Printers

The printer’s role as a quiet background device means it rarely gets attention from defenders. Meanwhile, it’s capable of:

• Storing previously scanned documents

• Sending email or file uploads through internal credentials

• Interacting with domain authentication systems

• Saving address books, passwords, and network shares

• Acting as a pivot point to other internal devices

A compromised printer can allow threat actors to monitor scanned content, intercept faxes, or quietly host malicious payloads. And because printers are usually left out of endpoint detection deployments, attackers may persist without triggering any alerts.

Why Manufacturers Are Still Behind

Printers today run on embedded operating systems like Linux or proprietary RTOS platforms. In theory, these platforms could be hardened like any other endpoint. In practice, manufacturers continue to:

• Ship with insecure defaults

• Enable legacy protocols like Telnet and FTP

• Avoid offering clear firmware update paths

• Provide little to no vulnerability disclosure support

• Rely on outdated security models not suited for modern threats

Firmware updates are often distributed through obscure vendor portals, lack verification mechanisms, and are rarely deployed in practice. Security bulletins are vague, and customer support teams frequently lack the knowledge to explain risks or mitigations.

While endpoint and server security has evolved rapidly in the last decade, printer security has barely moved. In many ways, printers are where routers were fifteen years ago powerful, connected, and dangerously neglected.

What Needs to Change

Printer manufacturers must take ownership of the risk their products introduce. That means:

• Disabling insecure services by default (FTP, Telnet, SNMPv1, VNC)

• Enforcing credential creation during setup

• Enabling automatic or at least alert-based firmware updates

• Improving logging and access monitoring

• Publishing vulnerability advisories with transparent timelines

• Providing proper documentation on hardening steps

Printers are no longer exempt from the responsibility of secure design. They are embedded computers attached to sensitive environments. Vendors must treat them accordingly.

What Organizations Can Do Today

Even without vendor cooperation, IT and security teams can take immediate steps to mitigate printer-related risks:

• Place printers on isolated VLANs with strict ACLs

• Disable unneeded services at the device or firewall level

• Change all factory-default credentials

• Monitor for open ports like 515, 9100, 23, 21, and 5900 internally

• Apply available firmware updates

• Configure audit logging and alerting, if supported

• Treat printers as endpoints in security scans

Even one poorly configured printer can become the entry point for a wider compromise.

Security teams must begin treating them with the same caution applied to desktops and cloud assets.

The Big Picture: Secure by Design Should Include Everything

Printers highlight a broader issue in cybersecurity that many connected devices are excluded from visibility and accountability simply because they seem boring or harmless.

The reality is that security should not depend on the perceived threat of the device. It should depend on its capabilities, its connectivity, and its ability to impact business continuity.

Printers scan legal documents, transmit confidential forms, and often authenticate to sensitive parts of the network. That is enough to warrant real, sustained attention not just from IT teams, but from the vendors that build and sell them.

The next time you walk past a printer, remember: it’s not just a box that spits out paper. It’s a networked computer with root access and no one watching.