# Vulnerability Assessment of Sensor Systems
###### Abstract
Relations between security and evaluation concepts: asset-threat-vulnerability-risk-countermeasure-evaluation-certifications-security assurance are discussed in Part 1/Section 7 of [5]. The assurance is based on the rigor applied during the development and manufacturing processes, independent third-party evaluation, and operation and maintenance according to the obtained certificate. IT products which are developed and evaluated in conformance with these requirements can be applied in higher risk environments. According to the Common Criteria methodology, the assurance is measurable using EALs (evaluation assurance levels) in the range of EAL1 to EAL7. This methodology has been broadly used for years. More than 2000 certification processes have been completed so far and the certificates have been granted to varied products or systems [6]. The Common Criteria methodology is defined on the general level and for this reason, it can be applied to any kind of IT product, but during the IT product development and evaluation processes, the distinctive characteristics and facilities of the IT product should be considered. This is performed by the identification of the IT product-related protected assets, vulnerabilities and threats, characteristics of the IT product operation environment, applications, risk, roles, etc. All this identified information is used to refine or supplement the Common Criteria development and evaluation processes, especially their input/output data. The methodology presented in the paper can be considered an example of the CC extension and refinement. With respect to the CC methodology, intelligent sensors can be considered relatively new and specific IT products. They have hardware (integrated circuits, electronic modules), firmware, network elements, and software (databases, applications) components and they co-operate with other IT systems. The risks related to the use of sensors in a broad range of business, industrial, health, and social applications should be taken into consideration. The mentioned heterogeneity, restricted power,processing, and communication resources, simplified security mechanisms, and specific threats and vulnerabilities strongly influence sensors' security development and evaluation. Please note that the number of certified sensors or sensor systems is currently low, though the demand for certified IT products, including sensors, IoT/IIoT (Internet of Things/Industrial Internet of Things) and other compact devices has been increasing recently. The Common Criteria application in sensors and sensor systems development are presented in [7; 8; 9; 10; 11; 12; 13; 14; 15] and will be discussed in the Section 2.3.1. Sensor products are similar to hardware security boxes distinguished by SOG-IS [16]. To meet this rising demand, the European cybersecurity certification schemes have been developed. The scheme integrates different evaluation/certification paths and assurance levels into one coherent scheme [17]. The research presented in the paper is consistent with these efforts. Sensor-specific vulnerabilities and attacks are discussed in numerous existing publications [18; 19; 20; 21], which can be used to form knowledge bases. The security evaluation and vulnerability assessment, especially in the Common Criteria domain, is presented in [22; 23; 24; 25; 26; 27; 28], which will be discussed in Section 2.3.2. The purpose of the work presented in the paper is to assess whether the vulnerability assessment specified in the Common Criteria methodology can be directly applied to sensors or whether it requires adaptation, and if so, what the range of this adaptation should be. Please note that the vulnerability assessment is the key task of the security evaluators. The main paper contribution is the sensor system vulnerability assessment method (SVAM) developed as the result of the above-mentioned research. SVAM is based on the proven Common Criteria methodology and considers sensor-specific issues.