A printer can run 1990s computer game Doom and spy on documents to establish a gateway into a network.
Speaking at 44CON in London, Mike Jordon, head of research at Context, said that the ability to compromise internet-connected devices raises more questions about security of the Internet of Things (IoT). At the conference, researchers successfully managed to remotely access the web interface on a Canon Pixma printer and modify firmware to run Doom.
“This latest example further demonstrates the insecurities posed by the emerging IoT as vendors rush to connect their devices,” said Jordon.
“The printer’s web interface did not require user authentication, allowing anyone to connect to it. But the real issue is with the firmware update process. If you can trigger a firmware update you can also change the web proxy settings and the DNS server; and if you can change these then you can redirect where the printer goes to check for a new firmware update and install custom code – in our case a copy of Doom.”
Context sampled 9,000 of the 32,000 IPs that Shodan indicated may have a vulnerable printer. Of these IPs, 1,822 responded and 122 indicated that they may have a firmware version that could be compromised. “Even if the printer is not connected directly to the internet on a user’s home network or on an office intranet, it is still vulnerable to remote attack,” said Jordon.
In its research, Context said that this interface does not require user authentication, allowing anyone to connect to the interface. “At first glance the functionality seems to be relatively benign, you could print out hundreds of test pages and use up all the ink and paper, so what? The issue is with the firmware update process.
“While you can trigger a firmware update you can also change the web proxy settings and the DNS server. If you can change these then you can redirect where the printer goes to check for a new firmware. So what protection does Canon use to prevent a malicious person from providing a malicious firmware? In a nutshell – nothing, there is no signing (the correct way to do it) but it does have very weak encryption.”
Canon thanked Context for detailing the vulnerability. In a statement, it said: “At Canon we work hard at securing all of our products, however with diverse and ever-changing security threats we welcome input from others to ensure our customers are as well protected as possible.
“We intend to provide a fix as quickly as is feasible. All PIXMA products launching from now onwards will have a username/password added to the PIXMA web interface, and models launched from the second half of 2013 onwards will also receive this update, models launched prior to this time are unaffected. This action will resolve the issue uncovered by Context.”
“We are not aware of anyone actively using this type of attack for malicious purposes but hopefully by raising awareness, we can encourage vendors to increase the security of this new generation of devices,” says Jordon. “Of course it is important to always apply the latest available firmware.”