Undercover (and vulnerable) computers

Printers can present a major privacy and security threat, argues Scott Bradner

It is hardly surprising that few pieces of electronics get built these days without one or more computers hidden inside. What is somewhat surprising is that too many of these computers are directly addressable on your network and are running Web or SNMP servers that can present significant hacking opportunities when imperfectly programmed. In many cases, they can also present significant threats to your privacy without any hacking required.

There seem to be Web and SNMP servers in everything (for example, Google gets 373,000 hits for "embedded Web server"). They show up in all sorts of network infrastructure gear, plug strips, home theater systems, environmental control systems, UPSs, test equipment, and, most relevant for this column, network-connected printers.

Some people have worried about the security threat of having a printer with a hackable computer in it for quite a while. The oldest story I ran across is from 1998 and I'm sure there are much older ones. More recently, security expert Brendan O'Connor gave a talk at last fall's Black Hat conference , which was reported on by Bruce Schneier

There are two problems these devices: they create a hackable computer inside your network's security perimeter, and in the case of printers, they can present a major privacy and security threat.

The hacking problem is made significantly worse by the fact that most people do not check software updates for printers. So even if the printer vendor were to put out a software update including a security fix, very few printers will get updated.

But the second problem cannot be addressed with a bug fix because the system is working as it was designed. For example, many medium to high-end workgroup printers now have disk drives where they store print jobs. They also have Web servers that users can interact with to schedule when jobs are to be printed or to reprint old jobs. Many of the printers only remove old print files when they run out of room on the disk. (At least one printer has an extra cost option that will purge day-old files -- the vendor wants you to pay extra for something that should come standard.)

Because printer manufacturers seem to think that everyone in a company is a saint, many of the printers let anyone who accesses the Web server print any file (and with a little hacking, maybe grab the file over the 'Net).

In many cases the person who installed the printer never knew it had a Web server in it. I speak from personal experience after just figuring out that my high-end Epson photo printer includes an automatically enabled Web server that is using the default password, which I have not figured out yet. Needless to say, the printer will be off and filtered until I can find out what the password is and reset it.

The lesson here is to find out how overly helpful a printer is and whether it meets your security and privacy rules before you buy and install it on your sensitive network.

Disclaimer: Harvard is all about lessons and I expect this one is being learned somewhere on campus. But the university has not expressed an opinion on too-smart printers -- I have.

Join the newsletter!

Error: Please check your email address.
Rocket to Success - Your 10 Tips for Smarter ERP System Selection
Keep up with the latest tech news, reviews and previews by subscribing to the Good Gear Guide newsletter.

Scott Bradner

Network World
Show Comments


James Cook University - Master of Data Science Online Course

Learn more >


Sansai 6-Outlet Power Board + 4-Port USB Charging Station

Learn more >

Victorinox Werks Professional Executive 17 Laptop Case

Learn more >



Back To Business Guide

Click for more ›

Most Popular Reviews

Latest Articles


PCW Evaluation Team

Louise Coady

Brother MFC-L9570CDW Multifunction Printer

The printer was convenient, produced clear and vibrant images and was very easy to use

Edwina Hargreaves

WD My Cloud Home

I would recommend this device for families and small businesses who want one safe place to store all their important digital content and a way to easily share it with friends, family, business partners, or customers.

Walid Mikhael

Brother QL-820NWB Professional Label Printer

It’s easy to set up, it’s compact and quiet when printing and to top if off, the print quality is excellent. This is hands down the best printer I’ve used for printing labels.

Ben Ramsden

Sharp PN-40TC1 Huddle Board

Brainstorming, innovation, problem solving, and negotiation have all become much more productive and valuable if people can easily collaborate in real time with minimal friction.

Sarah Ieroianni

Brother QL-820NWB Professional Label Printer

The print quality also does not disappoint, it’s clear, bold, doesn’t smudge and the text is perfectly sized.

Ratchada Dunn

Sharp PN-40TC1 Huddle Board

The Huddle Board’s built in program; Sharp Touch Viewing software allows us to easily manipulate and edit our documents (jpegs and PDFs) all at the same time on the dashboard.

Featured Content

Product Launch Showcase

Latest Jobs

Don’t have an account? Sign up here

Don't have an account? Sign up now

Forgot password?