Process industry dual-safety fusion risk quantitative evaluation method based on integration influence

Abstract

The invention relates to a process industry dual-safety fusion risk quantitative evaluation method based on integration influence, and the method specifically comprises the steps: determining a to-be-evaluated process industry workshop section, and constructing the connection topology of workshop section equipment according to the site deployment condition; sorting possible functional security and information security events and corresponding characteristics in a workshop section site, and sorting the events into threats and vulnerabilities of the industrial workshop section of the process to be evaluated in combination with related standards and general evaluation templates of the industry to which the events belong; establishing an association relationship between assets and vulnerabilities and an association relationship between vulnerabilities and threats according to the sorted threats and vulnerability entries and on-site workshop section equipment details; and calculating a double-safety fusion risk quantitative evaluation value of the industrial section of the process by fully considering the integration influence of different devices and connected devices thereof. The method can be different from a traditional industrial safety risk assessment method, and the risk quantitative assessment method is researched in a theoretical level by utilizing mutual integration influence and function and information safety events among process industrial equipment.

Description

Technical Field

[0001] The present invention relates to a quantitative risk assessment method for dual-safety integration of process industries based on integrated impact, which can utilize the continuous characteristics of the production process of process industries, fully consider the integrated impact between equipment, the mutual influence of functions and information security, and improve the accuracy of risk quantitative assessment, and belongs to the field of industrial control security. Background Art

[0002] With the deep integration of industrialization and informatization, industrial control systems have gradually moved from closed isolation to open interconnection. Combined with technologies such as 5G, the Internet of Things, and the Industrial Internet, they have improved production efficiency, but also brought security risks. In the open interconnection scenario, the network security risks of industrial control systems are further highlighted, especially for traditional relatively closed industrial control systems. Industrial control systems not only need to ensure functional safety, that is, to ensure that the system can respond safely when facing failures, but also need to ensure information security to prevent external attacks and data leakage. Early industrial control system designs did not fully consider information security, which led to attackers possibly affecting functional safety through network attacks, causing serious consequences. Accurate risk quantitative assessment is crucial to preventing and mitigating possible safety accidents. Through quantitative assessment, enterprises can identify and prioritize the most critical security risks and ensure the effective allocation and utilization of resources. In addition to technical protection, the security of industrial control systems also requires effective management measures, including asset management, configuration management, supply chain security, publicity and education, monitoring and early warning, emergency response, etc., to build a comprehensive security protection system. By integrating quantitative assessment methods of information security and functional safety, the risks of industrial control systems can be more comprehensively identified and controlled, thereby improving the reliability and stability of industrial production.

[0003] Most existing security risk assessment systems only analyze functional safety or information security, without considering the integration impact between process industry equipment and the interactive impact between functional safety and information security. Therefore, there is an urgent need for a set of information and functional dual safety fusion risk quantitative assessment methods that can discover problems in the network as a whole and fully analyze and evaluate the security status of industrial control systems from both functional safety and information security. Therefore, in the process of process industry system security risk assessment, how to achieve the organic integration of "functional safety + information security" is a huge challenge. Summary of the invention

[0004] In view of the above-mentioned technical deficiencies, the purpose of the present invention is to provide a quantitative assessment method for the dual-safety fusion risk of process industries based on integrated influence. By utilizing the mutual integrated influences between process industry equipment and functional and information security events, the dual-safety fusion risk of process industry sections is quantitatively assessed to promote the maintenance and protection of process industry safety.

[0005] The technical solution adopted by the present invention to achieve the above-mentioned purpose is:

[0006] A quantitative assessment method for dual safety fusion risk in process industry based on integrated impact includes the following steps:

[0007] 1) Determine the process industry section to be evaluated and build the connection topology of the section assets based on the on-site deployment;

[0008] 2) Based on industry standards and assessment templates, the functional safety and information security incidents that may occur at the work site and their corresponding characteristics are sorted into threats and vulnerabilities of the process industry work section to be assessed;

[0009] 3) Establish the relationship between assets and vulnerabilities, and between vulnerabilities and threats based on threat and vulnerability items and on-site equipment details;

[0010] 4) Utilize the relationship between assets and vulnerabilities, and between vulnerabilities and threats to calculate the quantitative assessment value of the dual-safety fusion risk of the process industrial section, and evaluate the risk of the industrial section based on the assessment value.

[0011] The step 1) is specifically:

[0012] The process industry section site is described as a weighted directed complex network as the connection topology of the section assets. The nodes in the network are individuals in the section that can send or receive products, data, and signals. The weight of each node is the importance of the node. If there is a directed edge between node a and node b, it means that there is a product, data, or signal from node a to node b.

[0013] The step 2) is specifically:

[0014] The threats and vulnerabilities of process industry sections are evaluated through three aspects: on-site conditions of the section, relevant industry standards, and general templates of process industries. Among them, the probability of occurrence of each threat needs to be defined, and the degree of harm of each vulnerability needs to be defined.

[0015] The step 3) comprises the following steps:

[0016] 3.1) Establish the relationship between assets and vulnerabilities: For each asset node in the directed complex network, determine the vulnerability involved in each asset node based on the on-site assessment of the on-site engineer;

[0017] 3.2) Establish the correlation between vulnerability and threat: For the threats and vulnerabilities involved in a certain work section, determine the vulnerability that each threat may cause based on the site engineer’s assessment of the site.

[0018] The step 4) comprises the following steps:

[0019] The risk quantitative assessment value TotalR of Shuangan Fusion is divided into two parts: direct risk DR and indirect risk IR, among which;

[0020] Let TotalR represent the quantitative assessment value of the dual-security fusion risk, DR and IR represent direct risk and indirect risk respectively, and α and β are the weights of the two risks.

[0021] 4.1) Determine the weight value according to the on-site conditions and assessment requirements;

[0022] 4.2) Calculate the quantitative assessment value of the dual-security fusion risk of a single node, TotalR, which is defined as:

[0023] TotalR=α×DR+β×IR

[0024] Among them, DR and IR represent direct risk and indirect risk respectively, and α and β represent the weights of the two risks;

[0025] 4.3) Assume that the asset list in the system is {1,2,...n,}, and the corresponding asset level is {A 1 ,A 2 ,...A n ,}, then the impact weight of each asset on the total risk value is: Assume that the total security risk value of the system is TotalR_system, then:

[0026] TotalR_system=∑ω i *TotalR i .

[0027] The direct risk is calculated based on the threats and vulnerabilities involved in the current node. Let the node weight be A and the probability level of threat i be T i , the vulnerability j is V j , then the direct risk value is:

[0028]

[0029] The indirect risk is related to the size of the attacked node and the affected area. Assuming that only nodes within 2 steps from the attacked node are considered to have indirect risk, an attack on a node a will cause indirect risk to all nodes in it. Assuming that the distance between nodes b, c, and d and the attacked node is 1 step, and the distance between nodes e, f, g, and h and the attacked node is 2 steps, the indirect risk is:

[0030]

[0031] Wherein, M and N are coefficients, M+N=1 and M>N.

[0032] The present invention has the following beneficial effects and advantages:

[0033] 1. The present invention utilizes the characteristics of vulnerability caused by threats in industrial scenarios, fully constructs the cross-influence between functional safety and information security events, identifies functional safety issues that may be induced by information security attacks, and thus forms a new failure mode.

[0034] 2. The present invention comprehensively considers the integrated impact between devices, distinguishes between direct risks and indirect risks, and emphasizes the security risk association and mutual influence between devices.

[0035] 3. The present invention reclassifies functional safety incidents and information security incidents according to threats and vulnerabilities, and realizes the integrated analysis of information security and functional safety. BRIEF DESCRIPTION OF THE DRAWINGS

[0036] Figure 1 It is a flow chart of the quantitative assessment method of dual safety fusion risk in process industry based on integrated impact;

[0037] Figure 2 It is a diagram of a weighted directed complex network;

[0038] Figure 3 It is a schematic diagram of the safety risk value calculation process based on integrated impact. DETAILED DESCRIPTION

[0039] The present invention is further described in detail below in conjunction with the accompanying drawings and embodiments.

[0040] The present invention proposes a quantitative assessment method for the dual-safety fusion risk of process industries based on integrated impact. By combining the mutual impact between equipment and between function and information security in process industries, it is different from traditional safety risk assessment methods. By fully considering the integrated impact of different equipment and the equipment connected to them, the quantitative assessment value of the dual-safety fusion risk of the process industry section is calculated.

[0041] The present invention provides an effective process industry dual-safety fusion risk quantitative assessment method based on integrated impact, which promotes the safety risk analysis of process industry systems.

[0042] like Figure 1 As shown, the specific steps include:

[0043] Step 1: Network the process industry section and build the connection topology of the section assets according to the on-site deployment. That is, set the equipment, software, applications, etc. in the section that can send or receive products, data, and signals as nodes. The weight of the node indicates the importance of the node to the section. If there is a product, data, or signal from node a to node b, there is a directed edge between node a and node b. Based on the above process, the weighted directed complex network can be constructed to describe the connection topology of the process industry site section, such as Figure 2 shown.

[0044] According to the actual structure of the on-site section of the process industry, a complex network can be constructed. According to the definition in the complex network, the on-site section of the process industry is abstracted as a complex network G = (V, E), where V is the set of asset nodes in the on-site section of the process industry, and E is the set of edges between asset nodes. The number of nodes n = |V| and the number of edges M = |E| are then set.

[0045] For example, for a process industry site section, the assets in the section, such as host computers, industrial control applications, databases, controllers, DCS, reactors, etc., can all be regarded as nodes. If there are connections such as actual production materials or data and signal transmission between these nodes, it means that there are edges between the node pairs.

[0046] Step 2: Sort out the functional safety and information security incidents and corresponding characteristics that may occur at the work site, and combine them with the relevant standards and general assessment templates of the industry to be evaluated to organize the threats and vulnerabilities of the process industry work section to be evaluated. The causes of possible risks are summarized from the two aspects of threats and vulnerabilities. The summarization method is divided into three aspects: the situation of the work site, relevant industry standards, and general templates for process industries. Each threat needs to define its probability of occurrence (the specific value of probability is 0-1), and each vulnerability needs to define its degree of harm (the degree of harm is 1-5, the higher the value, the higher the degree of harm).

[0047] The on-site conditions of a work section refer to the real-time status and environmental conditions of a specific work section or work area during the industrial production process, such as the number and distribution of on-site staff, the operating skills and training status of the staff, the availability of emergency facilities and safety equipment, the temperature, humidity, ventilation and lighting conditions of the work area, air quality and the concentration of hazardous substances, etc.

[0048] Relevant industry standards refer to the safety standards of the industry to which the assessed work section belongs, such as typical process industry standards (petroleum, chemical, building materials, etc.).

[0049] The general template for process industries refers to the common threat and vulnerability classifications in process industries, such as human threats, non-human threats, physical vulnerabilities, network vulnerabilities, and asset vulnerabilities.

[0050] Step 3: Based on the connection topology of the process industry field sections obtained in steps 1 and 2 and the threats and vulnerabilities of the process industry sections to be assessed, establish the association relationship between assets and vulnerabilities, and between vulnerabilities and threats. Specifically:

[0051] The relationship between assets and vulnerabilities: For each asset node in a directed complex network, the vulnerabilities involved in each asset node are determined based on the on-site engineer's assessment of the site. For a chemical industry section site, its host computer may involve certain physical vulnerabilities, such as physical access control, anti-theft and anti-destruction, waterproof and moisture-proof, etc. If the asset has such vulnerabilities, the asset is associated with the vulnerability.

[0052] Correlation between vulnerability and threat: For the threats and vulnerabilities involved in the work section, the vulnerability that each threat may cause is determined based on the site engineer's assessment of the site. Different threats may cause different vulnerabilities. For example, threats such as floods, typhoons, and geological disasters may cause vulnerabilities in waterproofing and moisture-proofing, which are associated here.

[0053] Step 4: Based on the above three steps, by fully considering the integration impact of different equipment and the equipment connected to it, calculate the quantitative assessment value of the dual safety integration risk of the process industrial section, such as Figure 3 shown.

[0054] The quantitative assessment value of dual-security fusion risk is divided into two parts: direct risk and indirect risk. Let TotalR represent the quantitative assessment value of dual-security fusion risk, DR and IR represent direct risk and indirect risk respectively, and α and β are the weights of the two risks. Before calculating the risk value, the weight value needs to be determined based on the on-site situation and assessment requirements. The quantitative assessment value of dual-security fusion risk of a single node is defined as:

[0055] TotalR=α×DR+β×IR

[0056] For example, if you are more concerned about direct risks, you can set α to a larger value, such as α=0.7, β=0.3.

[0057] The direct risk is calculated based on the threats and vulnerabilities involved in the node. The node weight is set to A; the probability level of threat i is T i ; The vulnerability j is V j , then the direct risk value is:

[0058]

[0059] The values ​​of probability level and vulnerability damage degree are both 1-5. The corresponding relationship between probability level and probability is shown in Table 1:

[0060] Table 1

[0061] Probability range 0-0.2 0.2-0.4 0.4-0.6 0.6-0.8 0.8-1 Probability level 1 2 3 4 5

[0062] Indirect risk is closely related to the size of the attacked node and the affected area. In this method, we assume that only nodes within 2 steps from the attacked node are considered to have indirect risk. An attack on a node a will cause indirect risk to all nodes in it, where nodes b, C, and d are assumed to be 1 step away from the attacked node, and nodes e, f, g, and h are 2 steps away from the attacked node, which can be expressed as

[0063]

[0064] According to the obtained direct risk value and indirect risk value, the safety risk value of each node can be obtained.

[0065] Assume that the asset list in the system is {1, 2, ... n,}, and the corresponding asset level is {A 1 , A 2 , ...A n ,} then the impact weight of each asset on the total risk value is: Assume that the total security risk value of the system is TotalR_system, then:

[0066] TotalR_system=∑ω i *TotalR i

[0067] Through this step, we will finally get the safety risk value of the process industry section.

[0068] Those skilled in the art will appreciate that the embodiments of the present application may be provided as methods, systems, or computer program products. Therefore, the present application may adopt the form of embodiments in combination with software and hardware. Moreover, the present application may adopt the form of a computer program product implemented on one or more computer-usable storage media (including but not limited to disk storage, CD-ROM, optical storage, etc.) that contain computer-usable program code.

[0069] The present application is described with reference to the method flow chart according to the embodiment of the present application. It should be understood that each process in the flow chart can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, a special-purpose computer, an embedded processor or other programmable data processing device to generate a machine, so that the instructions executed by the processor of the computer or other programmable data processing device generate instructions for implementing the process in the flow chart. Figure 1 A device that specifies functions in a process or multiple processes.

[0070] These computer program instructions may also be stored in a computer-readable memory capable of directing a computer or other programmable data processing device to operate in a specific manner, so that the instructions stored in the computer-readable memory produce an article of manufacture comprising an instruction device, which implements the process Figure 1 A function specified in a process or multiple processes.

[0071] These computer program instructions can also be loaded onto a computer or other programmable data processing device so that a series of operating steps are executed on the computer or other programmable device to produce a computer-implemented process, thereby providing instructions for implementing the process in the computer or other programmable device. Figure 1 The steps of a specified function in a process or multiple processes.

[0072] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention rather than to limit it. Although the present invention has been described in detail with reference to the above embodiments, ordinary technicians in the relevant field should understand that the specific implementation methods of the present invention can still be modified or replaced by equivalents. Any modification or equivalent replacement that does not depart from the spirit and scope of the present invention should be covered within the scope of protection of the claims of the present invention.

Claims

1. A quantitative assessment method for dual safety fusion risk in process industry based on integrated impact, characterized in that: The following steps are involved: 1) Determine the process industry section to be evaluated and build the connection topology of the section assets based on the on-site deployment; 2) Based on industry standards and assessment templates, the functional safety and information security incidents that may occur at the work site and their corresponding characteristics are sorted into threats and vulnerabilities of the process industry work section to be assessed; 3) Establish the relationship between assets and vulnerabilities, and between vulnerabilities and threats based on threat and vulnerability items and on-site equipment details; 4) Utilize the relationship between assets and vulnerabilities, and between vulnerabilities and threats to calculate the quantitative assessment value of the dual-safety fusion risk of the process industrial section, and evaluate the risk of the industrial section based on the assessment value.

2. According to the method of quantitative assessment of dual safety fusion risk in process industry based on integrated impact in claim 1, it is characterized in that: The step 1) is specifically: The process industry section site is described as a weighted directed complex network as the connection topology of the section assets. The nodes in the network are individuals in the section that can send or receive products, data, and signals. The weight of each node is the importance of the node. If there is a directed edge between node a and node b, it means that there is a product, data, or signal from node a to node b.

3. According to the method of quantitative assessment of dual safety fusion risk in process industry based on integrated impact in claim 1, it is characterized in that: The step 2) is specifically: The threats and vulnerabilities of process industry sections are evaluated through three aspects: on-site conditions of the section, relevant industry standards, and general templates of process industries. Among them, the probability of occurrence of each threat needs to be defined, and the degree of harm of each vulnerability needs to be defined.

4. According to the method of quantitative assessment of dual safety fusion risk in process industry based on integrated impact in claim 1, it is characterized in that: The step 3) comprises the following steps: 3.1) Establish the relationship between assets and vulnerabilities: For each asset node in the directed complex network, determine the vulnerability involved in each asset node based on the on-site assessment of the on-site engineer; 3.2) Establish the correlation between vulnerability and threat: For the threats and vulnerabilities involved in a certain work section, determine the vulnerability that each threat may cause based on the site engineer’s assessment of the site.

5. According to the method of quantitative assessment of dual safety fusion risk in process industry based on integrated impact in claim 1, it is characterized in that: The step 4) comprises the following steps: The risk quantitative assessment value TotalR of Shuangan Fusion is divided into two parts: direct risk DR and indirect risk IR, among which; Let TotalR represent the quantitative assessment value of the dual-security fusion risk, DR and IR represent direct risk and indirect risk respectively, and α and β are the weights of the two risks. 4.1) Determine the weight value according to the on-site conditions and assessment requirements; 4.2) Calculate the quantitative assessment value of the dual-security fusion risk of a single node, TotalR, which is defined as: TotalR=α×DR+β×IR Among them, DR and IR represent direct risk and indirect risk respectively, and α and β represent the weights of the two risks; 4.3) Assume that the asset list in the system is {1,2,...n,}, and the corresponding asset level is {A1,A2,...A n ,}, then the impact weight of each asset on the total risk value is: Assume that the total security risk value of the system is TotalR_system, then: TotalR_system=∑ω i *TotalR i 。 6. The method for quantitatively assessing dual safety risks in process industries based on integrated impact according to claim 5 is characterized in that: The direct risk is calculated based on the threats and vulnerabilities involved in the current node. Let the node weight be A and the probability level of threat i be T i , the vulnerability j is V j , then the direct risk value is:

7. The method for quantitatively assessing dual safety risks in process industries based on integrated impact according to claim 5 is characterized in that: The indirect risk is related to the size of the attacked node and the affected area. Assuming that only nodes within 2 steps from the attacked node are considered to have indirect risk, an attack on a node a will cause indirect risk to all nodes in it. Assuming that the distance between nodes b, c, and d and the attacked node is 1 step, and the distance between nodes e, f, g, and h and the attacked node is 2 steps, the indirect risk is: Wherein, M and N are coefficients, M+N=1 and M>N.

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