Editorial disclosure: Top 10 Printer is an independent site. Rankings are based solely on manufacturer specifications — we don't accept payment for placement or earn affiliate commissions. Read about our editorial independence
HomePrinter HelpNetwork Printer Security and Privacy
Security

Network Printer Security and Privacy

Networked printers are full computers and deserve basic security attention. This guide covers protecting the printer's administration, understanding certificate warnings, secure printing, sensible network rules, monitoring, and the data printers can retain — written to inform without encouraging unsafe shortcuts.

Last reviewed: October 2026

Safe first checks

  1. 1Read and note the exact message on the printer display or in the print queue.
  2. 2Print the printer's own test or configuration page to help distinguish a device problem from a computer problem.
  3. 3Record custom settings before removing a printer or reinstalling a driver; ask IT first on managed work devices.
  4. 4Stop using the printer if there is excessive heat, smoke, a burning smell, sparks, or leaks. Disconnect power only if safe; never touch wet or damaged electrical parts.

Default administrator credentials or internet-exposed printers

A printer still using its default administrator password, or one reachable from the public internet, is an easy target. Its settings and stored data could be changed or read by others.

Possible causes

  • •An unchanged default admin password
  • •The printer's admin page reachable from outside the network
  • •Port forwarding exposing the printer
  • •No access control on management

What to check

  1. 1.Change the default administrator password to a strong, unique one.
  2. 2.Keep the printer on your private network, not reachable from the internet.
  3. 3.Remove any port forwarding that exposes the printer externally.
  4. 4.Limit who can reach the printer's management interface.

When to stop: do not open printer management to the public internet. On managed networks, credential and exposure policies are set by IT — coordinate with them rather than changing network rules yourself.

Invalid certificate warnings on the printer's administration interface

Your browser warns that the printer's administration page has an invalid or untrusted certificate. Many printers ship with self-signed certificates, which browsers flag by default.

Possible causes

  • •A self-signed or expired printer certificate
  • •A certificate not trusted by your browser
  • •A hostname mismatch
  • •An outdated certificate after a name/address change

What to check

  1. 1.Confirm you are connecting to the correct printer address on your own network.
  2. 2.Understand that many printers use self-signed certificates, which browsers warn about.
  3. 3.If your environment manages certificates, have a proper one installed per policy.
  4. 4.Keep printer firmware current so certificate handling is up to date.

When to stop: treat certificate warnings carefully; do not blindly bypass them, especially on networks you do not control. On managed networks, let IT handle printer certificates rather than ignoring warnings as a habit.

Secure print or PIN-release setup

Secure print holds a job until you enter a PIN or authenticate at the printer, so sensitive pages do not sit in the tray. Setting it up adds a privacy layer on shared printers.

Possible causes

  • •Prerequisite: a printer and driver that support secure/PIN print
  • •Prerequisite: the feature enabled in driver settings
  • •Prerequisite: a PIN or credential set for release
  • •Prerequisite: access to the printer to release jobs

What to check

  1. 1.Enable secure or PIN printing in the driver's properties if available.
  2. 2.Set a PIN when sending a sensitive job.
  3. 3.Release the job at the printer by entering the PIN.
  4. 4.Collect the pages promptly after release.

When to stop: PIN release keeps pages from sitting in the tray, but it does not by itself mean every network connection is encrypted. For highly sensitive material, follow your organization's data-handling policy.

Network rules blocking printing on ports such as 9100 or 631

Printing uses specific network ports (for example 9100 for raw printing or 631 for IPP). Security rules may block these, so jobs do not reach the printer.

Possible causes

  • •Firewall rules blocking printing ports
  • •The printer on a segment where those ports are closed
  • •Security software restricting printing traffic
  • •A policy limiting printing protocols

What to check

  1. 1.Confirm whether others can print (points to a shared rule).
  2. 2.Check that your device and the printer are on segments where printing is permitted.
  3. 3.Prefer standard, current printing protocols (such as IPP) the network allows.
  4. 4.Work with whoever manages the network to permit printing appropriately.

When to stop: do not broadly open printer ports to the public internet or disable the firewall to force printing. Port rules exist for safety; adjust them only through proper network management.

SNMP monitoring problems

SNMP lets software monitor printer status (like supply levels) over the network. When it is misconfigured or blocked, status monitoring fails or the driver reports the printer unavailable.

Possible causes

  • •SNMP disabled or blocked on the network
  • •A community/credential mismatch
  • •A driver's SNMP status check timing out
  • •Security policy restricting SNMP

What to check

  1. 1.If only status monitoring fails, check whether the driver's SNMP status option is causing timeouts.
  2. 2.Confirm SNMP settings match between the printer and monitoring software.
  3. 3.Ensure the network permits SNMP where it is needed.
  4. 4.Keep monitoring to trusted systems on your own network.

When to stop: SNMP configuration on managed networks is IT's responsibility. Do not enable broad SNMP access or weaken settings to make monitoring work — coordinate with IT.

Documents or data retained on the printer

Printers and multifunction devices can store print, scan, copy, and fax data, sometimes on an internal drive. That stored data is a privacy consideration, especially before disposal or return.

Possible causes

  • •Jobs cached in printer memory or storage
  • •Scan/fax history retained on the device
  • •An internal storage drive holding data
  • •Address books or credentials saved on the printer

What to check

  1. 1.Clear stored jobs and history through the printer's menu where available.
  2. 2.Before disposal or return, use any built-in data-clear or reset that wipes stored data per the manual.
  3. 3.Remove saved address books and credentials from the device.
  4. 4.Limit what sensitive data is sent to shared or storage-equipped printers.

When to stop: secure data erasure on storage-equipped printers is model-specific and, for high-sensitivity environments, a task for IT or a qualified process. Follow your organization's disposal policy rather than assuming a simple reset clears everything.

Preventive habits

  • Change default admin passwords to strong, unique ones.
  • Keep printers on your private network, never exposed to the internet.
  • Use secure/PIN print for confidential documents.
  • Keep printer firmware current for security fixes.
  • Clear stored data before disposing of or returning a printer.

Frequently asked questions

Related printer-type guides

Laser Printers Multifunction Printers