Biblio

Cyber incidents are occurring every day using various attack strategies. Deploying security solutions with strong configurations will reduce the attack surface and improve the forensic readiness, but will increase the security overhead and cost. In contrast, using moderate or low security configurations will reduce that overhead, but will inevitably decrease the investigation readiness. To avoid the use of cost-prohibitive approaches in developing forensic-ready systems, we present in this paper a game theoretic approach for deploying an investigation-ready infrastructure. The proposed game is a non-cooperative two-player game between an adaptive cyber defender that uses a cognitive security solution to increase the investigation readiness and reduce the attackers' untraceability, and a cyber attacker that wants to execute non-provable attacks with a low cost. The cognitive security solution takes its strategic decision, mainly based on its ability to make forensic experts able to differentiate between provable identifiable, provable non-identifiable, and non-provable attack scenarios, starting from the expected evidences to be generated. We study the behavior of the two strategic players, looking for a mixed Nash equilibrium during competition and computing the probabilities of attacking and defending. A simulation is conducted to prove the efficiency of the proposed model in terms of the mean percentage of gained security cost, the number of stepping stones that an attacker creates and the rate of defender false decisions compared to two different approaches.

In this paper, we study system security against Advanced Persistent Threats (APTs). APTs are stealthy and persistent but APTs interact with system and introduce information flows in the system as data-flow and control-flow commands. Dynamic Information Flow Tracking (DIFT) is a promising detection mechanism against APTs which taints suspicious input sources in the system and performs online security analysis when a tainted information is used in unauthorized manner. Our objective in this paper is to model DIFT that handle data-flow and conditional branches in the program that arise from control-flow commands. We use game theoretic framework and provide the first analytical model of DIFT with data-flow and conditional-branch tracking. Our game model which is an undiscounted infinite-horizon stochastic game captures the interaction between APTs and DIFT and the notion of conditional branching. We prove that the best response of the APT is a maximal reachability probability problem and provide a polynomial-time algorithm to find the best response by solving a linear optimization problem. We formulate the best response of the defense as a linear optimization problem and show that an optimal solution to the linear program returns a deterministic optimal policy for the defense. Since finding Nash equilibrium for infinite-horizon undiscounted stochastic games is computationally difficult, we present a nonlinear programming based polynomial-time algorithm to find an E-Nash equilibrium. Finally, we perform experimental analysis of our algorithm on real-world data for NetRecon attack augmented with conditional branching.

Traditional power grid security schemes are being replaced by highly advanced and efficient smart security schemes due to the advancement in grid structure and inclusion of cyber control and monitoring tools. Smart attackers create physical, cyber, or cyber-physical attacks to gain the access of the power system and manipulate/override system status, measurements and commands. In this paper, we formulate the environment for the attacker-defender interaction in the smart power grid. We provide a strategic analysis of the attacker-defender strategic interaction using a game theoretic approach. We apply repeated game to formulate the problem, implement it in the power system, and investigate for optimal strategic behavior in terms of mixed strategies of the players. In order to define the utility or cost function for the game payoffs calculation, generation power is used. Attack-defense budget is also incorporated with the attacker-defender repeated game to reflect a more realistic scenario. The proposed game model is validated using IEEE 39 bus benchmark system. A comparison between the proposed game model and the all monitoring model is provided to validate the observations.

Today's network is distributed and heterogeneous in nature and has numerous applications which affect day to day life, such as e-Banking, e-Booking of tickets, on line shopping etc. Hence the security of the network is crucial. Threats in the network can be due to intrusions. Such threats can be observed and handled using Intrusion Detection System. The security can be achieved using intrusion detection system, which observes the data traffic and identifies it as an intrusion or not. The objective of this paper is to design a model using game theoretic approach for intrusion detection. Game model is designed by defining players, strategies and utility functions to identify the Probe attacks. This model is tested with NSLKDD data set. The model is the Probe attacks are identified by dominated strategies elimination method. Experimental results shows that game model identifies the attacks with good detection rate.

The installation of a protection system can provide protection by either deterring or stopping an attacker. Both modes of effectiveness-deterring and stopping-are uncertain. Some have guessed that deterrence plays a much bigger role than stopping force. The force of deterrence should therefore be of considerable interest, especially if its effect could be estimated and incorporated into a larger risk analysis and business case for developing and buying new systems, but nowhere has it been estimated quantitatively. The effect of one type of deterrence, namely, influencing an attacker's choice of targets-or target shifting, biasing an attacker away from some targets toward others-is assessed quantitatively here using a game-theoretic approach. It is shown that its positive effects are significant. It features as a force multiplier on the order of magnitude or more, even for low-performance security countermeasures whose effectiveness may be compromised somewhat, of necessity, in order to keep the number of false alarms serviceably low. The analysis furthermore implies that there are certain minimum levels of stopping performance that a protection should provide in order to avoid attracting the choice of attackers (under deterrence). Nothing in the analysis argues for complacency in security. Developers must still design the best affordable systems. The analysis enters into the middle ground of security, between no protection and impossibly perfect protection. It counters the criticisms that some raise about lower-level, affordable, sustainable measures that security providers naturally gravitate toward. Although these measures might in some places be defeated in ways that a non-expert can imagine, the measures are not for that reason irresponsible or to be dismissed. Their effectiveness can be much greater than they first appear.