Two security researchers uncovered a series of vulnerabilities that attackers could exploit to control implanted pacemakers remotely.
At Black Hat USA, researchers Billy Rios of security firm Whitescope and Jonathan Butts of QED Secure Solutions unveiled a chain of vulnerabilities in the CareLink 2090 Programmer. The weaknesses specifically affect the software delivery network for the pacemaker, which is made by medical device manufacturer Medtronic. Rios and Butts found that the updates pushed by the network are neither encrypted nor signed. These flaws make it possible for an attacker to quietly release a malicious update that could alter the number of shocks delivered by the device, reports Komando. Such alterations could potentially prove fatal to patients using the device.
As Medtronic’s software delivery network consists of proprietary cloud infrastructure, the researchers recognized it would have been illegal for them to break into that system and verify their vulnerabilities. They therefore mapped the system and created their own replica of the environment. Through this exercise, they were able to confirm the presence of the flaws.
Rios and Butts reported the bugs to Medtronic in January 2017. Their expectation was that the medical device company would patch the issues. But it has not fixed the issues as of this publication. Instead it released a security bulletin in February 2018 claiming that the researchers’ findings “revealed no new potential safety risks based on the existing product security risk assessment.” Medtronic repeated this line in a subsequent statement published in June 2018, indicating that a product update wasn’t necessary and that users could mitigate the risks by following the CareLink 2090 Programmer reference manual and connecting to a secure network.
Butts rejected this response as ineffective. As quoted by WIRED:
“The time period Medtronic spent discussing this with us, if they had just put that time into making a fix they could have solved a lot of these issues. Now we’re two years down the road and there are patients still susceptible to this risk of altering therapy, which means we could do a shock when we wanted to or we could deny shocks from happening. It’s very frustrating.”
Rios agreed with Butts’ assessment, noting that “if you just code sign, all these issues go away, but for some reason they refuse to do that.” He went on to tell Ars Technica that Medtronic’s response doesn’t make the jobs of security researchers any easier.
“We believe the benefits for implanted medical devices outweigh the risks. However, when you have manufacturers acting the way Medtronic did, it’s hard to trust them.”
The vulnerabilities found by Rios and Butts highlights the importance of organizations and other sectors using HTTPS to secure their communications with proprietary technology and systems. To ensure the security of those connections, security professionals need to make sure their digital certificates are safe from misuse. Complete visibility of the encryption environment is a good place to start for information security personnel.