Embedded Systems Academy

Some people try to push easily-available “Internet-proven security mechanisms” also into embedded networks like CAN and CANopen. However, in embedded systems security is never about a single network, one needs to look at the entire picture.

We have started a series of articles about embedded security issues with a focus on CAN and CANopen networks in the CAN newsletter. In the current article we are having a closer look at taxi fare calculation as one example for an attractive hacking target. How can you be sure that you are not overcharged? What would be required to make taxi fare manipulations really difficult?

Tampering with the underlying CAN/CANopen communication is just one of several attack vectors available here. Besides manipulating the wheel with the sensor – knowing that a 3% change in diameter can result in a 10% variance in the fare calculation – there is also the sealed meter. But these days, technology like 3D printers and sophisticated electronics are also easily being used by the “bad guys”. From the article:

“Think about the manipulations already performed today to banking machines. Additional keyboards and card readers can be tacked-on to banking machines in a way that users don’t recognize the difference. In the same way a meter-like display could be designed to clip onto or fully around an existing meter. The original meter “vanishes” inside a fake meter that can display whatever the taxi driver would like it to display.”

Browse the current CAN Newsletter: March 2018

Read the full article here: Security expectations vs.limitations (pdf)