Assessing and augmenting SCADA cyber security: a survey of techniques

SCADA systems monitor and control critical infrastructures of national importance such as power generation and distribution, water supply, transportation networks, and manufacturing facilities. The pervasiveness, miniaturisations and declining costs of internet connectivity have transformed these systems from strictly isolated to highly interconnected networks. The connectivity provides immense benefits such as reliability, scalability and remote connectivity, but at the same time exposes an otherwise isolated and secure system, to global cyber security threats. This inevitable transformation to highly connected systems thus necessitates effective security safeguards to be in place as any compromise or downtime of SCADA systems can have severe economic, safety and security ramifications. One way to ensure vital asset protection is to adopt a viewpoint similar to an attacker to determine weaknesses and loopholes in defences. Such mind sets help to identify and fix potential breaches before their exploitation. This paper surveys tools and techniques to uncover SCADA system vulnerabilities. A comprehensive review of the selected approaches is provided along with their applicability

Intrusion detection and prevention of web service attacks for software as a service:Fuzzy association rules vs fuzzy associative patterns

Cloud computing inherits all the systems, networks as well asWeb Services’ security vulnerabilities, in particular for software as a service (SaaS), where business applications or services are provided over the Cloud as Web Service (WS). Hence, WS-based applications must be protected against loss of integrity, confidentiality and availability when they are deployed over to the Cloud environment. Many existing IDP systems address only attacks mostly occurring at PaaS and IaaS. In this paper, we present our fuzzy association rule-based (FAR) and fuzzy associative pattern-based (FAP) intrusion detection and prevention (IDP) systems in defending against WS attacks at the SaaS level. Our experimental results have validated the capabilities of these two IDP systems in terms of detection of known attacks and prediction of newvariant attacks with accuracy close to 100%. For each transaction transacted over the Cloud platform, detection, prevention or prediction is carried out in less than five seconds. For load and volume testing on the SaaS where the system is under stress (at a work load of 5000 concurrent users submitting normal, suspicious and malicious transactions over a time interval of 300 seconds), the FAR IDP system provides close to 95% service availability to normal transactions. Future work involves determining more quality attributes besides service availability, such as latency, throughput and accountability for a more trustworthy SaaS

Support Vector Machine IDS Rule Extraction Mechanism from Honeypot Data

As awareness is increasing rapidly, more upto date aggressions are appearing. Security is a key to protection above all these problems. In this work, we will make a real existence scenario, employing honeypots. Honeypot is a well projected arrangement that entices hackers into it. By baiting the hacker into the arrangement, it is probable to monitor the procedures that are commenced and running on the arrangement by hacker. In supplementary words, honeypot is a mislead contraption that looks like a real arrangement in order to appeal the attacker. The target of the honeypot is analyzing, understanding, discerning and pursuing hacker’s behaviors in order to craft extra safeguard systems. Honeypot is outstanding method to enhance web protection administrators’ vision and discover how to become data from a victim arrangement employing forensic tools. Honeypot is additionally extremely functional for upcoming menaces to retain trail of new knowledge aggressions

Towards automated incident handling: how to select an appropriate response against a network-based attack?

The increasing amount of network-based attacks evolved to one of the top concerns responsible for network infrastructure and service outages. In order to counteract these threats, computer networks are monitored to detect malicious traffic and initiate suitable reactions. However, initiating a suitable reaction is a process of selecting an appropriate response related to the identified network-based attack. The process of selecting a response requires to take into account the economics of an reaction e.g., risks and benefits. The literature describes several response selection models, but they are not widely adopted. In addition, these models and their evaluation are often not reproducible due to closed testing data. In this paper, we introduce a new response selection model, called REASSESS, that allows to mitigate network-based attacks by incorporating an intuitive response selection process that evaluates negative and positive impacts associated with each countermeasure. We compare REASSESS with the response selection models of IE-IRS, ADEPTS, CS-IRS, and TVA and show that REASSESS is able to select the most appropriate response to an attack in consideration of the positive and negative impacts and thus reduces the effects caused by an network-based attack. Further, we show that REASSESS is aligned to the NIST incident life cycle. We expect REASSESS to help organizations to select the most appropriate response measure against a detected network-based attack, and hence contribute to mitigate them

Information Security Analysis and Auditing of IEC61850 Automated Substations

This thesis is about issues related to the security of electric substations automated by IEC61850, an Ethernet (IEEE 802.3) based protocol. It is about a comprehen­ sive security analysis and development of a viable method of auditing the security of this protocol. The security analysis focuses on the possible threats to an electric substation based on the possible motives of an attacker. Existing methods and met­ rics for assessing the security of computer networks are explored and examined for suitability of use with IEC61850. Existing methods and metrics focus on conven­ tional computers used in computer networks which are fundamentally different from Intelligent Electronic Devices (IED’s) of substations in terms of technical composition and functionality. Hence, there is a need to develop a new method of assessing the security of such devices. The security analysis is then used to derive a new metric scheme to assess the security of IED’s that use IEC61850. This metric scheme is then tested out in a sample audit on a real IEC61850 network and compared with two other commonly used security metrics. The results show that the new metric is good in assessing the security of IED’s themselves. Further analysis on IED security is done by conducting simulated cyber attacks. The results are then used to develop an Intrusion Detection System (IDS) to guard against such attacks. The temporal risk of intrusion on an electric substation is also evaluated

Detection of Denial of Service Attacks against Domain Name System Using Neural Networks

Along with the explosive growth of the Internet, the demand for efficient and secure Internet Infrastructure has been increasing. For the entire chain of Internet connectivity the Domain Name System (DNS) provides name to address mapping services. Hackers exploit this fact to damage different parts of Internet. In order to prevent this system from different types of attacks, we need to prepare a classification of possible security threats against DNS. This dissertation focuses on Denial of Service (DoS) attacks as the major security issue during last years, and gives an overview of techniques used to discover and analyze them. The process of detection and classification of DoS against DNS has been presented in two phases in our model. The proposed system architecture consists of a statistical pre-processor and a machine learning engine. The first step in our work was to generate the DNS traffic in normal and attack situations for using as the input of our intrusion detection system (IDS). With the prior knowledge of DoS attacks against DNS, we used a network simulator to model DNS traffic with high variability. Therefore, the difficulty of creating different scenarios of attacks in a real environment has been decreased. The pre-processor, processes the collected data statistically and derives the final variable values. These parameters are the inputs of the detector engine. In the current research for our machine learning engine, we aimed to find the optimum machine learning algorithm to be used as an IDS. The performance of our system was measured in terms of detection rate, accuracy, and false alarm rate. The results indicated that the three layered back propagation neural network with a 3-7-3 structure provides a detection rate of 99.55% for direct DoS attacks and 97.82% for amplification DoS attacks. It can give us 99% accuracy and an acceptable false alarm rate of 0.28% comparing to other types of classifiers

Intrusion detection and management over the world wide web

As the Internet and society become ever more integrated so the number of Internet users continues to grow. Today there are 1.6 billion Internet users. They use its services to work from home, shop for gifts, socialise with friends, research the family holiday and manage their finances. Through generating both wealth and employment the Internet and our economies have also become interwoven. The growth of the Internet has attracted hackers and organised criminals. Users are targeted for financial gain through malware and social engineering attacks. Industry has responded to the growing threat by developing a range defences: antivirus software, firewalls and intrusion detection systems are all readily available. Yet the Internet security problem continues to grow and Internet crime continues to thrive. Warnings on the latest application vulnerabilities, phishing scams and malware epidemics are announced regularly and serve to heighten user anxiety. Not only are users targeted for attack but so too are businesses, corporations, public utilities and even states. Implementing network security remains an error prone task for the modern Internet user. In response this thesis explores whether intrusion detection and management can be effectively offered as a web service to users in order to better protect them and heighten their awareness of the Internet security threat

Hardware Acceleration of Network Intrusion Detection System Using FPGA

This thesis presents new algorithms and hardware designs for Signature-based Network Intrusion Detection System (SB-NIDS) optimisation exploiting a hybrid hardwaresoftware co-designed embedded processing platform. The work describe concentrates on optimisation of a complete SB-NIDS Snort application software on a FPGA based hardware-software target rather than on the implementation of a single functional unit for hardware acceleration. Pattern Matching Hardware Accelerator (PMHA) based on Bloom filter was designed to optimise SB-NIDS performance for execution on a Xilinx MicroBlaze soft-core processor. The Bloom filter approach enables the potentially large number of network intrusion attack patterns to be efficiently represented and searched primarily using accesses to FPGA on-chip memory. The thesis demonstrates, the viability of hybrid hardware-software co-designed approach for SB-NIDS. Future work is required to investigate the effects of later generation FPGA technology and multi-core processors in order to clearly prove the benefits over conventional processor platforms for SB-NIDS. The strengths and weaknesses of the hardware accelerators and algorithms are analysed, and experimental results are examined to determine the effectiveness of the implementation. Experimental results confirm that the PMHA is capable of performing network packet analysis for gigabit rate network traffic. Experimental test results indicate that our SB-NIDS prototype implementation on relatively low clock rate embedded processing platform performance is approximately 1.7 times better than Snort executing on a general purpose processor on PC when comparing processor cycles rather than wall clock time

Improving intrusion detection systems using data mining techniques

Recent surveys and studies have shown that cyber-attacks have caused a lot of damage to organisations, governments, and individuals around the world. Although developments are constantly occurring in the computer security field, cyber-attacks still cause damage as they are developed and evolved by hackers. This research looked at some industrial challenges in the intrusion detection area. The research identified two main challenges; the first one is that signature-based intrusion detection systems such as SNORT lack the capability of detecting attacks with new signatures without human intervention. The other challenge is related to multi-stage attack detection, it has been found that signature-based is not efficient in this area. The novelty in this research is presented through developing methodologies tackling the mentioned challenges. The first challenge was handled by developing a multi-layer classification methodology. The first layer is based on decision tree, while the second layer is a hybrid module that uses two data mining techniques; neural network, and fuzzy logic. The second layer will try to detect new attacks in case the first one fails to detect. This system detects attacks with new signatures, and then updates the SNORT signature holder automatically, without any human intervention. The obtained results have shown that a high detection rate has been obtained with attacks having new signatures. However, it has been found that the false positive rate needs to be lowered. The second challenge was approached by evaluating IP information using fuzzy logic. This approach looks at the identity of participants in the traffic, rather than the sequence and contents of the traffic. The results have shown that this approach can help in predicting attacks at very early stages in some scenarios. However, it has been found that combining this approach with a different approach that looks at the sequence and contents of the traffic, such as event- correlation, will achieve a better performance than each approach individually

Discrete Moving Target Defense Application and Benchmarking in Software-Defined Networking

Moving Target Defense is a technique focused on disrupting certain phases of a cyber-attack. The static nature of the existing networks gives the adversaries an adequate amount of time to gather enough data concerning the target and succeed in mounting an attack. The random host address mutation is a well-known MTD technique that hides the actual IP address from external scanners. When the host establishes a session of transmitting or receiving data, due to mutation interval, the session is interrupted, leading to the host’s unavailability. Moving the network configuration creates overhead on the controller and additional switching costs resulting in latency, poor performance, packet loss, and jitter. In this dissertation, we proposed a novel discrete MTD technique in software-defined networking (SDN) to individualize the mutation interval for each host. The host IP address is changed at different intervals to avoid the termination of the existing sessions and to increase complexity in understanding mutation intervals for the attacker. We use the flow statistics of each host to determine if the host is in a session of transmitting or receiving data. Individualizing the mutation interval of each host enhances the defender game strategy making it complex in determining the pattern of mutation interval. Since the mutation of the host address is achieved using a pool of virtual (temporary) host addresses, a subnet game strategy is introduced to increase complexity in determining the network topology. A benchmarking framework is developed to measure the performance, scalability, and reliability of the MTD network with the traditional network. The analysis shows the discrete MTD network outperforms the random MTD network in all tests