There is a public report of a vulnerability in the Controller Area Network (CAN) Bus standard with proof-of-concept (PoC) exploit code affecting CAN Bus, a broadcast-based network standard, according to a report with ICS-CERT.
Researchers Andrea Palanca, Eric Evenchick, Federico Maggi, and Stefano Zanero identified a vulnerability exploiting a weakness in the CAN protocol that allows an attacker to perform a denial-of-service (DoS) attack. The public report was coordinated with ICS-CERT prior to its release.
ICS-CERT notified some affected vendors, primarily auto manufacturers and entities within the healthcare industry, about the report to confirm the vulnerability and to identify mitigations.
ICS-CERT is issuing this alert to provide notice of the report and identify baseline mitigations for reducing risks to these and other cybersecurity attacks.
The report included vulnerability details and PoC exploit code for a resource exhaustion vulnerability that could result on a denial of service (DoS). The exploit focused on automobiles would require physical access to leverage the vulnerability.
CAN is widely used throughout the critical manufacturing, healthcare and public health, and transportation systems sectors.
Successful exploitation of the vulnerability on an automobile may allow an attacker with physical access and extensive knowledge of CAN to reverse engineer network traffic to perform a DoS attack disrupting the availability of arbitrary functions of the targeted device.
The severity of the attack varies depending on how the CAN is implemented on a system and how easily an input port (typically ODB-II) can be accessed by a potential attacker. This attack differs from previously reported frame-based attacks, which are typically detected by IDS/IPS systems. The exploit focuses on recessive and dominate bits to cause malfunctions in CAN nodes rather than complete frames.
The CAN bus protocol is used widely by the automotive industry and other industries; however, the impact and exploitability of the identified vulnerability is dependent on the implementation and controls.
The only current recommendation for protecting against this exploit is to limit access to input ports (specifically ODB-II) on automobiles. ICS-CERT is currently coordinating with vendors and security researchers to identify mitigations.