Biblio
We consider the possibility of detecting malicious behaviors of the advanced persistent threat (APT) at endpoints during incident response or forensics investigations. Specifically, we study the case where third-party sensors are not available; our observables are obtained solely from inherent digital artifacts of Windows operating systems. What is of particular interest is an artifact called the Application Compatibility Cache (Shimcache). As it is not apparent from the Shimcache when a file has been executed, we propose an algorithm of estimating the time of file execution up to an interval. We also show guarantees of the proposed algorithm's performance and various possible extensions that can improve the estimation. Finally, combining this approach with methods of machine learning, as well as information from other digital artifacts, we design a prototype system called XTEC and demonstrate that it can help hunt for the APT in a real-world case study.
Advance persistent threat is a primary security concerns to the big organizations and its technical infrastructure, from cyber criminals seeking personal and financial information to state sponsored attacks designed to disrupt, compromising infrastructure, sidestepping security efforts thus causing serious damage to organizations. A skilled cybercriminal using multiple attack vectors and entry points navigates around the defenses, evading IDS/Firewall detection and breaching the network in no time. To understand the big picture, this paper analyses an approach to advanced persistent threat by doing the same things the bad guys do on a network setup. We will walk through various steps from foot-printing and reconnaissance, scanning networks, gaining access, maintaining access to finally clearing tracks, as in a real world attack. We will walk through different attack tools and exploits used in each phase and comparative study on their effectiveness, along with explaining their attack vectors and its countermeasures. We will conclude the paper by explaining the factors which actually qualify to be an Advance Persistent Threat.
In recent years, cyber attacks have caused substantial financial losses and been able to stop fundamental public services. Among the serious attacks, Advanced Persistent Threat (APT) has emerged as a big challenge to the cyber security hitting selected companies and organisations. The main objectives of APT are data exfiltration and intelligence appropriation. As part of the APT life cycle, an attacker creates a Point of Entry (PoE) to the target network. This is usually achieved by installing malware on the targeted machine to leave a back-door open for future access. A common technique employed to breach into the network, which involves the use of social engineering, is the spear phishing email. These phishing emails may contain disguised executable files. This paper presents the disguised executable file detection (DeFD) module, which aims at detecting disguised exe files transferred over the network connections. The detection is based on a comparison between the MIME type of the transferred file and the file name extension. This module was experimentally evaluated and the results show a successful detection of disguised executable files.
Understanding and fending off attack campaigns against organizations, companies and individuals, has become a global struggle. As today's threat actors become more determined and organized, isolated efforts to detect and reveal threats are no longer effective. Although challenging, this situation can be significantly changed if information about security incidents is collected, shared and analyzed across organizations. To this end, different exchange data formats such as STIX, CyBOX, or IODEF have been recently proposed and numerous CERTs are adopting these threat intelligence standards to share tactical and technical threat insights. However, managing, analyzing and correlating the vast amount of data available from different sources to identify relevant attack patterns still remains an open problem. In this paper we present Mantis, a platform for threat intelligence that enables the unified analysis of different standards and the correlation of threat data trough a novel type-agnostic similarity algorithm based on attributed graphs. Its unified representation allows the security analyst to discover similar and related threats by linking patterns shared between seemingly unrelated attack campaigns through queries of different complexity. We evaluate the performance of Mantis as an information retrieval system for threat intelligence in different experiments. In an evaluation with over 14,000 CyBOX objects, the platform enables retrieving relevant threat reports with a mean average precision of 80%, given only a single object from an incident, such as a file or an HTTP request. We further illustrate the performance of this analysis in two case studies with the attack campaigns Stuxnet and Regin.
The extensive use of information and communication technologies in power grid systems make them vulnerable to cyber-attacks. One class of cyber-attack is advanced persistent threats where highly skilled attackers can steal user authentication information's and then move laterally in the network, from host to host in a hidden manner, until they reach an attractive target. Once the presence of the attacker has been detected in the network, appropriate actions should be taken quickly to prevent the attacker going deeper. This paper presents a game theoretic approach to optimize the defense against an invader attempting to use a set of known vulnerabilities to reach critical nodes in the network. First, the network is modeled as a vulnerability multi-graph where the nodes represent physical hosts and edges the vulnerabilities that the attacker can exploit to move laterally from one host to another. Secondly, a two-player zero-sum Markov game is built where the states of the game represent the nodes of the vulnerability multi-graph graph and transitions correspond to the edge vulnerabilities that the attacker can exploit. The solution of the game gives the optimal strategy to disconnect vulnerable services and thus slow down the attack.
Detecting botnets and advanced persistent threats is a major challenge for network administrators. An important component of such malware is the command and control channel, which enables the malware to respond to controller commands. The detection of malware command and control channels could help prevent further malicious activity by cyber criminals using the malware. Detection of malware in network traffic is traditionally carried out by identifying specific patterns in packet payloads. Now bot writers encrypt the command and control payloads, making pattern recognition a less effective form of detection. This paper focuses instead on an effective anomaly based detection technique for bot and advanced persistent threats using a data mining approach combined with applied classification algorithms. After additional tuning, the final test on an unseen dataset, false positive rates of 0% with malware detection rates of 100% were achieved on two examined malware threats, with promising results on a number of other threats.
Cloud storage is vulnerable to advanced persistent threats (APTs), in which an attacker launches stealthy, continuous, well-funded and targeted attacks on storage devices. In this paper, cumulative prospect theory (CPT) is applied to study the interactions between a defender of cloud storage and an APT attacker when each of them makes subjective decisions to choose the scan interval and attack interval, respectively. Both the probability weighting effect and the framing effect are applied to model the deviation of subjective decisions of end-users from the objective decisions governed by expected utility theory, under uncertain attack durations. Cumulative decision weights are used to describe the probability weighting effect and the value distortion functions are used to represent the framing effect of subjective APT attackers and defenders in the CPT-based APT defense game, rather than discrete decision weights, as in earlier prospect theoretic study of APT defense. The Nash equilibria of the CPT-based APT defense game are derived, showing that a subjective attacker becomes risk-seeking if the frame of reference for evaluating the utility is large, and becomes risk-averse if the frame of reference for evaluating the utility is small.
In a world where highly skilled actors involved in cyber-attacks are constantly increasing and where the associated underground market continues to expand, organizations should adapt their defence strategy and improve consequently their security incident management. In this paper, we give an overview of Advanced Persistent Threats (APT) attacks life cycle as defined by security experts. We introduce our own compiled life cycle model guided by attackers objectives instead of their actions. Challenges and opportunities related to the specific camouflage actions performed at the end of each APT phase of the model are highlighted. We also give an overview of new APT protection technologies and discuss their effectiveness at each one of life cycle phases.
Abstract—Lateral movement-based attacks are increasingly leading to compromises in large private and government networks, often resulting in information exfiltration or service disruption. Such attacks are often slow and stealthy and usually evade existing security products. To enable effective detection of such attacks, we present a new approach based on graph-based modeling of the security state of the target system and correlation of diverse indicators of anomalous host behavior. We believe that irrespective of the specific attack vectors used, attackers typically establish a command and control channel to operate, and move in the target system to escalate their privileges and reach sensitive areas. Accordingly, we identify important features of command and control and lateral movement activities and extract them from internal and external communication traffic. Driven by the analysis of the features, we propose the use of multiple anomaly detection techniques to identify compromised hosts. These methods include Principal Component Analysis, k-means clustering, and Median Absolute Deviation-based utlier detection. We evaluate the accuracy of identifying compromised hosts by using injected attack traffic in a real enterprise network dataset, for various attack communication models. Our results show that the proposed approach can detect infected hosts with high accuracy and a low false positive rate.
Existing security mechanisms for managing the Internet infrastructural resources like IP addresses, AS numbers, BGP advertisements and DNS mappings rely on a Public Key Infrastructure (PKI) that can be potentially compromised by state actors and Advanced Persistent Threats (APTs). Ideally the Internet infrastructure needs a distributed and tamper-resistant resource management framework which cannot be subverted by any single entity. A secure, distributed ledger enables such a mechanism and the blockchain is the best known example of distributed ledgers. In this paper, we propose the use of a blockchain based mechanism to secure the Internet BGP and DNS infrastructure. While the blockchain has scaling issues to be overcome, the key advantages of such an approach include the elimination of any PKI-like root of trust, a verifiable and distributed transaction history log, multi-signature based authorizations for enhanced security, easy extensibility and scriptable programmability to secure new types of Internet resources and potential for a built in cryptocurrency. A tamper resistant DNS infrastructure also ensures that it is not possible for the application level PKI to spoof HTTPS traffic.
Targeted attacks on IT systems are a rising threat against the confidentiality of sensitive data and the availability of systems and infrastructures. Planning for the eventuality of a data breach or sabotage attack has become an increasingly difficult task with the emergence of advanced persistent threats (APTs), a class of highly sophisticated cyber-attacks that are nigh impossible to detect using conventional signature-based systems. Understanding, interpreting, and correlating the particulars of such advanced targeted attacks is a major research challenge that needs to be tackled before behavior-based approaches can evolve from their current state to truly semantics-aware solutions. Ontologies offer a versatile foundation well suited for depicting the complex connections between such behavioral data and the diverse technical and organizational properties of an IT system. In order to facilitate the development of novel behavior-based detection systems, we present TAON, an OWL-based ontology offering a holistic view on actors, assets, and threat details, which are mapped to individual abstracted events and anomalies that can be detected by today's monitoring data providers. TOAN offers a straightforward means to plan an organization's defense against APTs and helps to understand how, why, and by whom certain resources are targeted. Populated by concrete data, the proposed ontology becomes a smart correlation framework able to combine several data sources into a semantic assessment of any targeted attack.
We propose a modular framework which deploys state-of-the art techniques in dynamic pattern matching as well as machine learning algorithms for Big Data predictive and be-havioural analytics to detect threats and attacks in Managed File Transfer and collaboration platforms. We leverage the use of the kill chain model by looking for indicators of compromise either for long-term attacks as Advanced Persistent Threats, zero-day attacks or DDoS attacks. The proposed engine can act complimentary to existing security services as SIEMs, IDS, IPS and firewalls.
Growth of internet era and corporate sector dealings communication online has introduced crucial security challenges in cyber space. Statistics of recent large scale attacks defined new class of threat to online world, advanced persistent threat (APT) able to impact national security and economic stability of any country. From all APTs, botnet is one of the well-articulated and stealthy attacks to perform cybercrime. Botnet owners and their criminal organizations are continuously developing innovative ways to infect new targets into their networks and exploit them. The concept of botnet refers collection of compromised computers (bots) infected by automated software robots, that interact to accomplish some distributed task which run without human intervention for illegal purposes. They are mostly malicious in nature and allow cyber criminals to control the infected machines remotely without the victim's knowledge. They use various techniques, communication protocols and topologies in different stages of their lifecycle; also specifically they can upgrade their methods at any time. Botnet is global in nature and their target is to steal or destroy valuable information from organizations as well as individuals. In this paper we present real world botnet (APTs) survey.
Red teams play a critical part in assessing the security of a network by actively probing it for weakness and vulnerabilities. Unlike penetration testing - which is typically focused on exploiting vulnerabilities - red teams assess the entire state of a network by emulating real adversaries, including their techniques, tactics, procedures, and goals. Unfortunately, deploying red teams is prohibitive: cost, repeatability, and expertise all make it difficult to consistently employ red team tests. We seek to solve this problem by creating a framework for automated red team emulation, focused on what the red team does post-compromise - i.e., after the perimeter has been breached. Here, our program acts as an automated and intelligent red team, actively moving through the target network to test for weaknesses and train defenders. At its core, our framework uses an automated planner designed to accurately reason about future plans in the face of the vast amount of uncertainty in red teaming scenarios. Our solution is custom-developed, built on a logical encoding of the cyber environment and adversary profiles, using techniques from classical planning, Markov decision processes, and Monte Carlo simulations. In this paper, we report on the development of our framework, focusing on our planning system. We have successfully validated our planner against other techniques via a custom simulation. Our tool itself has successfully been deployed to identify vulnerabilities and is currently used to train defending blue teams.