Page 18 - Cyber Defense eMagazine - November 2017

The CAN protocol issues an error message to recall the message with the intentionally incorrect
bit. These steps are repeated. The substantial number of errors creates a Bus Off state. In
theory, the protocol should isolate a device that would be malfunctioning. This would stop the
waterfall of other devices continuing to fail post the initial device. The increase in the number of
errors creates the Bus Off state.

The attacker may focus on the different modules in the vehicle for the attack. With a successful
attack, the airbags, anti-lock brakes, door locks, or other areas in the vehicle may be disabled
(Greenberg, 2017).

Remediation

In the non-vehicle realm, the remediation for this is not a complex issue to solve. There are a
number of applications that may work well with the use case in the enterprise. These, while
coded for the enterprise, accomplishes its task exceptionally well, do not work in the vehicle
technology environment. To correct this and would require an update to the CAN standard
(Maggi, 2017). There are many different configurations to attempt to correct this, including
segmenting the network in the vehicle and encryption.

Reference

Greenberg, A. (2017, August 16). A deep flaw in your car lets hackers shut down safety
features. Retrieved from https://www.wired.com/story/car-hack-sht-down-safety-features/

Kovacs, E. (2017, July 31). ICS-CERT warns of CANBus vulnerability. Retrieved from
http://www.securityweek.com/ics-cert-warns-can-bus-vulnerability

Maggi, F. (2017, August 16). The crisis of connected cars: When vulnerabilities affect the CAN
standard. Retrieved from http://blog.trendmicro.com/trendlabs-security-intelligence/connected-
car-hack/

Palanca, A., Evenchick, E., Maggi, F., & Zanero, S. (2017, June 4). A stealth, selective, link-
layer denial-of-service attack against automotive networks. Retrieved from
https://link.springer.com/chapter/0.1007/978-3-319-60876-1_9

About the Author

DRP is a Cybersecurity Lab Engineer focused on securing the world for the users one module
at a time. DRP’s interests include the intersection AI & ML and automotive cybersecurity.

18 Cyber Defense eMagazine – November 2017 Edition
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