A Bayesian Attack-Network Modeling Approach to Mitigating Malware-Based Banking Cyberattacks

According to Cybersecurity Ventures, the damage related to cybercrime is projected to reach $6 trillion annually by 2021. The majority of the cyberattacks are directed at financial institutions as this reduces the number of intermediaries that the attacker needs to attack to reach the target - monetary proceeds. Research has shown that malware is the preferred attack vector in cybercrimes targeted at banks and other financial institutions. In light of the above, this paper presents a Bayesian Attack Network modeling technique of cyberattacks in the financial sector that are perpetuated by crimeware. We use the GameOver Zeus malware for our use cases as it’s the most common type of malware in this domain. The primary targets of this malware are any users of financial services. Today, financial services are accessed using personal laptops, institutional computers, mobile phones and tablets, etc. All these are potential victims that can be enlisted to the malware’s botnet. In our approach, phishing emails as well as Common Vulnerabilities and Exposures (CVEs) which are exhibited in various systems are employed to derive conditional probabilities that serve as inputs to the modeling technique. Compared to the state-of-the-art approaches, our method generates probability density curves of various attack structures whose semantics are applied in the mitigation process. This is based on the level exploitability that is deduced from the vertex degrees of the compromised nodes that characterizes the probability density curves.