Biblio

Modbus TCP/IP protocol is a commonly used protocol in industrial automation control systems, systems responsible for sensitive operations such as gas turbine operation and refinery control. The protocol was designed decades ago with no security features in mind. Denial of service attack and malicious parameter command injection are examples of attacks that can exploit vulnerabilities in industrial control systems that use Modbus/TCP protocol. This paper discusses and explores the use of intrusion detection and prevention systems (IDPS) with deep packet inspection (DPI) capabilities and DPI industrial firewalls that have capability to detect and stop highly specialized attacks hidden deep in the communication flow. The paper has the following objectives: (i) to develop signatures for IDPS for common attacks on Modbus/TCP based network architectures; (ii) to evaluate performance of three IDPS - Snort, Suricata and Bro - in detecting and preventing common attacks on Modbus/TCP based control systems; and (iii) to illustrate and emphasize that the IDPS and industrial firewalls with DPI capabilities are not preventing but only mitigating likelihood of exploitation of Modbus/TCP vulnerabilities in the industrial and automation control systems. The results presented in the paper illustrate that it might be challenging task to achieve requirements on real-time communication in some industrial and automation control systems in case the DPI is implemented because of the latency and jitter introduced by these IDPS and DPI industrial firewall.

Cybersecurity assurance plays an important role in managing trust in smart grid communication systems. In this paper, cybersecurity assurance controls for smart grid communication networks and devices are delineated from the more technical functional controls to provide insights on recent innovative risk-based approaches to cybersecurity assurance in smart grid systems. The cybersecurity assurance control baselining presented in this paper is based on requirements and guidelines of the new family of IEC 62443 standards on network and systems security of industrial automation and control systems. The paper illustrates how key cybersecurity control baselining and tailoring concepts of the U.S. NIST SP 800-53 can be adopted in smart grid security architecture. The paper outlines the application of IEC 62443 standards-based security zoning and assignment of security levels to the zones in smart grid system architectures. To manage trust in the smart grid system architecture, cybersecurity assurance base lining concepts are applied per security impact levels. Selection and justification of security assurance controls presented in the paper is utilizing the approach common in Security Technical Implementation Guides (STIGs) of the U.S. Defense Information Systems Agency. As shown in the paper, enhanced granularity for managing trust both on the overall system and subsystem levels of smart grid systems can be achieved by implementation of the instructions of the CNSSI 1253 of the U.S. Committee of National Security Systems on security categorization and control selection for national security systems.

Application whitelisting software allows only examined and trusted applications to run on user's machine. Since many malicious files don't require administrative privileges in order for them to be executed, whitelisting can be the only way to block the execution of unauthorized applications in enterprise environment and thus prevent infection or data breach. In order to assess the current state of such solutions, the access to three whitelisting solution licenses was obtained with the purpose to test their effectiveness against different modern types of ransomware found in the wild. To conduct this study a virtual environment was used with Windows Server and Enterprise editions installed. The objective of this paper is not to evaluate each vendor or make recommendations of purchasing specific software but rather to assess the ability of application control solutions to block execution of ransomware files, as well as assess the potential for future research. The results of the research show the promise and effectiveness of whitelisting solutions.