Oak Ridge National Laboratory
Abstract:Modern vehicles are complex cyber-physical systems made of hundreds of electronic control units (ECUs) that communicate over controller area networks (CANs). This inherited complexity has expanded the CAN attack surface which is vulnerable to message injection attacks. These injections change the overall timing characteristics of messages on the bus, and thus, to detect these malicious messages, time-based intrusion detection systems (IDSs) have been proposed. However, time-based IDSs are usually trained and tested on low-fidelity datasets with unrealistic, labeled attacks. This makes difficult the task of evaluating, comparing, and validating IDSs. Here we detail and benchmark four time-based IDSs against the newly published ROAD dataset, the first open CAN IDS dataset with real (non-simulated) stealthy attacks with physically verified effects. We found that methods that perform hypothesis testing by explicitly estimating message timing distributions have lower performance than methods that seek anomalies in a distribution-related statistic. In particular, these "distribution-agnostic" based methods outperform "distribution-based" methods by at least 55% in area under the precision-recall curve (AUC-PR). Our results expand the body of knowledge of CAN time-based IDSs by providing details of these methods and reporting their results when tested on datasets with real advanced attacks. Finally, we develop an after-market plug-in detector using lightweight hardware, which can be used to deploy the best performing IDS method on nearly any vehicle.
Abstract:The Controller Area Network (CAN) protocol is ubiquitous in modern vehicles, but the protocol lacks many important security properties, such as message authentication. To address these insecurities, a rapidly growing field of research has emerged that seeks to detect tampering, anomalies, or attacks on these networks; this field has developed a wide variety of novel approaches and algorithms to address these problems. One major impediment to the progression of this CAN anomaly detection and intrusion detection system (IDS) research area is the lack of high-fidelity datasets with realistic labeled attacks, without which it is difficult to evaluate, compare, and validate these proposed approaches. In this work we present the first comprehensive survey of publicly available CAN intrusion datasets. Based on a thorough analysis of the data and documentation, for each dataset we provide a detailed description and enumerate the drawbacks, benefits, and suggested use cases. Our analysis is aimed at guiding researchers in finding appropriate datasets for testing a CAN IDS. We present the Real ORNL Automotive Dynamometer (ROAD) CAN Intrusion Dataset, providing the first dataset with real, advanced attacks to the existing collection of open datasets.
Abstract:There is a lack of scientific testing of commercially available malware detectors, especially those that boast accurate classification of never-before-seen (zero-day) files using machine learning (ML). The result is that the efficacy and trade-offs among the different available approaches are opaque. In this paper, we address this gap in the scientific literature with an evaluation of commercially available malware detection tools. We tested each tool against 3,536 total files (2,554 72% malicious, 982 28% benign) including over 400 zero-day malware, and tested with a variety of file types and protocols for delivery. Specifically, we investigate three questions: Do ML-based malware detectors provide better detection than signature-based detectors? Is it worth purchasing a network-level malware detector to complement host-based detection? What is the trade-off in detection time and detection accuracy among commercially available tools using static and dynamic analysis? We present statistical results on detection time and accuracy, consider complementary analysis (using multiple tools together), and provide a novel application of a recent cost-benefit evaluation procedure by Iannaconne \& Bridges that incorporates all the above metrics into a single quantifiable cost to help security operation centers select the right tools for their use case. Our results show that while ML-based tools are more effective at detecting zero-days and malicious executables, they work best when used in combination with a signature-based solution. In addition, network-based tools had poor detection rates on protocols other than the HTTP or SMTP, making them a poor choice if used on their own. Surprisingly, we also found that all the tools tested had lower than expected detection rates, completely missing 37% of malicious files tested and failing to detect any polyglot files.