Securing an HP Printer

Just like a computer, a printer can be used to attack a network and the computers connected to that network. Most networked Hewlett Packard (HP) printers come with a utility you can use to secure your printer, reducing the risk of it being used as a gateway to the network. This utility also protects against unwanted print jobs coming through the network.

Use one of the following applications to secure your HP printer:

HyperTerminal (for Windows)
Secure Telnet (for Windows or Macintosh)

Before you begin:

Read Access Control List (ACL) Caveats.
Find your building's Gateway IP address and subnet mask number.

Access Control List (ACL) Caveats

You may specify no more than 10 IP and/or subnet numbers.
You cannot remove individual IP/subnet numbers. To remove numbers, you must clear the entire list and then re-enter the updated list of numbers.
If your building's IP/subnet number changes, and you fail to enter the new number before the change, you must "cold reset" and reconfigure the printer to regain access.
If a password is not set, anyone in the trusted IP range(s) can reset the list.
If you forget the password, you will have to "cold reset" the printer to regain access.

HyperTerminal (for Windows)

Go to Start> Run. The Run window appears.
In the Open field, type hypertrm and click OK. HyperTerminal will start, and the Connection Description window appears.
In the Name field, type printer and click OK. The Connect To window appears.
In the Connect Using drop down list, select TCP/IP(Winsock). In the Host Address field, type the IP address for the printer (leave Port field as is) and click OK.
A response similar to Please type '?' for HELP or '/' for current settings appears.
From the File menu in the HyperTerminal window, select Properties and click the Settings tab. Click the ASCII Setup button. Click to checkmark the box for Echo Typed Characters Locally. This setting allows the keyboard strokes to display. Note: The backspace key will not delete characters. Use the arrow key to move the curser back and type new characters to overwrite existing characters.
Click OK in the ASCII Setup window and click OK in the Properties window.
At the > prompt, type allow: and your building's Gateway IP and subnet mask number,
e.g., allow: 129.24.8.0 255.255.248.0
Press <Enter> and repeat for each additional pair of numbers until you have completed the Access Control List (ACL).

Note: Your building's Gateway IP address should end in zero (0). If it doesn't, change the last number to a zero.

If the computers connecting to the printer have static IPs, type allow: and the IP number,
e.g., allow: 129.xx.xx.xx and press <Enter>.
When you are finished entering the IP/subnet numbers in the ACL, type allow: list and press <Enter> to review the ACL. If you find errors, type allow: 0 (zero) and press <Enter>. This will clear the ACL, and you can re-enter the correct numbers (repeat step 8). You cannot remove individual numbers.
At the > prompt, type passwd and press <Enter>. Create a password and press <Enter>. Make a note of the printer's password and keep it in a secure location so that others in authority in your area can have access to it.
At the > prompt, type quit and press <Enter>. This will close the configuration utility and save your changes.
When prompted to save your session, click No and quit HyperTerminal.

Secure Telnet (for Windows or Macintosh)

Start your Secure Telnet/Terminal program and log in, linux or linux.unm.edu
At the $ prompt, type telnet and the IP address for the printer, e.g., telnet 129.xx.xx.xx and press <Enter> ( <return> on a Macintosh) .
A response similar to Please type '?' for HELP or '/' for current settings appears.
At the $ prompt, type allow: and ITS' machine room Gateway IP and subnet mask number, i.e., allow: 129.24.8.0 255.255.248.0 and press <Enter> (<return>). Repeat the allow command with your building's Gateway IP and subnet number. Repeat for each additional pair of numbers until you have completed the Access Control List (ACL).

Note: Your building's Gateway IP address should end in zero (0). If it doesn't, change the last number to a zero.

If the computers connecting to the printer have static IPs, type allow: and the IP number,
e.g., allow: 129.xx.xx.xx and press <Enter> (<return>).
When you are finished entering the IP/subnet numbers in the ACL, type allow: list and press <Enter> (<return>) to review the ACL. If you find errors, type allow: 0 (zero) and press <Enter> (<return>). This will clear the ACL, and you can re-enter the correct numbers (repeat step 3). You cannot remove individual numbers.
At the $ prompt, type passwd and press <Enter> (<return>) . Create a password and press <Enter> (<return>) . Make a note of the printer's password and keep in a secure location so that others in authority in your area can have access to it.
At the $ prompt, type quit and press <Enter> (<return>). This will close the configuration utility and save your changes.
Log out and quit Secure Telnet/Terminal.