No abstract

With the occurrence of cyber security incidents, the value of threat intelligence is coming to the fore. Timely extracting Indicator of Compromise (IOC) from cyber threat intelligence can quickly respond to threats. However, the sparse text in public threat intelligence scatters useful information, which makes it challenging to assess unstructured threat intelligence. In this paper, we proposed Cyber Threat Intelligence Automated Assessment Model (TIAM), a method to automatically assess highly sparse threat intelligence from multiple dimensions. TIAM implemented automatic classification of threat intelligence based on feature extraction, defined assessment criteria to quantify the value of threat intelligence, and combined ATT&CK to identify attack techniques related to IOC. Finally, we associated the identified IOCs, ATT&CK techniques, and intelligence quantification results. The experimental results shown that TIAM could better assess threat intelligence and help security managers to obtain valuable cyber threat intelligence.

Threat modeling and simulation (TMS) was aimed at dynamically capturing the features of attacks, which is a challenging job in complex Industrial Internet of Things (IIoT) control systems due to the complicated relationships among attacks. Recently, Meta Attack Language (MAL) showed its powerful TMS capabilities for representing complex attacks. However, existing methods pay less attention to the impact of changes in threat profiles on the simulation of key attack techniques. This paper proposes a novel method called threat response modeling language (TRMLang) for threat modeling and simulation in complex IIoT attacks. TRMLang obtains attacker information through an automated analysis of cyber threat intelligence (CTI) to build dynamic attacker profiles. Furthermore, it merges attacker features and probabilistic attack graphs in the simulation to improve TMS performance. The experimental results demonstrate that TRMLang can represent and evaluate the security conditions of IIoT control systems with two attack cases by Lazarus Group on SEGRID smart grids.