KR100755000B1 - Security risk management system and method - Google Patents

Abstract

The present invention relates to a security risk management system and method, comprising a part of calculating a risk impact and level after qualitative risk calculation in a risk management evaluation process step, and when protection measures are established or not, or different protections. Compared with the selection of measures, it is possible to select the optimal solution with the best risk reduction results. When a series of processes are carried out according to the project management procedure, each process is given a role, developed as a tool, and the tool is used, the existing risk management results can be reduced while the evaluation period is shorter than the conventional method. It will be automated. In addition, in the present invention, the risk analysis performed by various evaluators to search for information online between the evaluators and to review the opinions of other evaluators in advance to minimize the false evaluation alone. To this end, the present invention includes a higher risk analysis model, a lower risk analysis model, a damage calculation model, a risk management engine server, a questionnaire server, a risk calculation algorithm, a damage calculation algorithm, and a database schema for each database list.

Information security risk management, asset analysis, threat analysis, vulnerability analysis, risk calculation, damage calculation

Description

SECURITY RISK MANAGEMENT SYSTEM AND METHOD}

1 is a block diagram of a security risk management system according to an embodiment of the present invention;

2 is a damage calculation graph according to an embodiment of the present invention,

3 is a table showing the total asset information for the information and communication infrastructure according to an embodiment of the present invention,

4 is a security risk analysis diagram according to an embodiment of the present invention,

5 is a process screen of the risk management processor according to an embodiment of the present invention;

6 is a questionnaire server screen of the security risk management system according to an embodiment of the present invention,

7a to 7c is a map for analyzing the importance of data, applications, servers according to an embodiment of the present invention,

8 is a map for identifying a connection configuration of a server, an application, and data according to an embodiment of the present invention;

9A to 9D are maps for analyzing importance of mapped data, applications, and servers according to one embodiment of the present invention;

FIG. 10 is a table illustrating criticality of data, applications, and servers according to an embodiment of the present invention.

11a and 11b is a time-varying risk analysis graph according to an embodiment of the present invention,

12A to 12C are state block diagrams according to one embodiment of the present invention;

13A and 13B are graphs showing damage analysis of unit assets according to one embodiment of the present invention;

14 is a damage and recovery diagram for the information communication infrastructure according to an embodiment of the present invention.

<Explanation of symbols for main parts of the drawings>

100: high level risk analysis module

200: low level risk analysis module

300: damage calculation module

400: risk management engine server

401-404: risk analysis database

500: Survey Server

501, 502: Survey Server Database

600: evaluation officer terminal

601: evaluator terminal

602: manager terminal

603: operator terminal

The present invention relates to a security risk management system and method, and more particularly, to include a damage assessment portion in a qualitative evaluation method to reflect a part of the quantitative portion, and to evaluate the evaluator with expertise in place and time online. The present invention relates to a security risk management system and method for performing an evaluation without receiving and ensuring immediateness on the comparison and analysis of protection measures.

In general, risk management for information systems has different advantages and disadvantages in using quantitative or qualitative methods. In the qualitative method, the subjective view of the evaluator works a lot and there can be many differences depending on the evaluation point. In the quantitative method, it is not easy to identify the asset and to estimate the value of the asset. And most of the existing risk management techniques are handwritten, so there is no criterion to determine whether the optimal protection measures have been established despite the considerable amount of time spent in manpower. In particular, it is very difficult to estimate asset value because information and communication infrastructure is very large and interlocks with other facilities.

Current risk management (analysis) processes are mainstream, identifying risks and vulnerabilities, identifying risks and vulnerabilities for unit assets, calculating risks, and becoming the de facto standard model. However, evaluation activities in such risk management have a very subjective perspective in estimating asset value, asset level, threat level, vulnerability level, and countermeasure cost, and thus have limited reliability in evaluating the value of information assets. .

On the other hand, in the basic idea of information security, managers demand a cost-effective effect, and they are interested in how much damage can be reduced compared to when the protection measures are taken and not established.

In addition, the existing security risk management system requires one evaluator to organize all the results. As a result, they do not know what the other evaluators have given, and the opinions of various evaluators tend to be ignored. Therefore, there is a need for a method of providing various data in one risk management engine server and managing the entire evaluation result so that all of the evaluators can select and decide. In this case, the contents of the minority evaluation can be reviewed later. In addition, in the case of information and communication infrastructure, it is not located in one place but is scattered in several regions. Therefore, evaluators may not be able to gather and express opinions in one place, and thus there is a limit in collecting the overall evaluation results.

Conventional techniques in this field include GMITS (MIST) developed by NIST in the United States, CSE in Canada, BS7799 in the UK, and CRAMM, but they only describe risk management methods, but also discuss and evaluate opinions. The decision is not defined. In addition, there is an inconvenience that the overall system configuration is not made or has to be developed limitedly to work by hand.

As such, existing technologies have the following problems in performing risk analysis.

First, risk analysis is divided into qualitative and quantitative methods according to the approach, which requires a lot of manpower and cost to process both methods simultaneously.

Second, to establish a protection plan based on the results of risk analysis, it is necessary to establish an information security solution. It is not only difficult to select the optimal solution, but also to compare the different types of solutions. It should be confirmed that there is no solution for this.

Third, in the risk management field, some risks remain due to information security solutions, and it is necessary to decide in a short time whether to accept these risks or to take countermeasures.

Fourth, risk analysis requires many evaluators to meet a large number of interviewees and due diligence on a number of assets. Individual management of these assessments results in insufficient review and even inadequate review. There is a problem that proceeds with the process.

Lastly, by evaluating relevant information remotely and inquiring the evaluation results of the counterparts in order to prevent personal errors, the evaluation results of evaluators are managed so that a few opinions can be identified. This lacks the immediateness of the evaluator's environment.

Accordingly, the present invention has been made to solve the above-mentioned problems of the prior art, and an object of the present invention is to include a damage estimation field in an existing risk management processor and define a process so that the evaluator can evaluate the evaluator at risk analysis. They provide a security risk management system and method that can perform assessments regardless of location and time, as well as to ensure immediateness of the results of the comparison and analysis of safeguards.

Security risk management system of the present invention for achieving the above object, a high-level risk analysis module for estimating the level of information protection in response to the data delivered from the evaluator terminal, and the detailed and detailed security of the level of information protection When planning risk management, the low-level risk analysis module that performs risk analysis and classifying the protected object into confidentiality, integrity and availability, and provide the corresponding information protection measures, which are expected when the information protection measures are introduced. It is a damage estimation module that analyzes the cost-effectiveness by calculating the level of risk reduction, analyzes the impact of damage by creating various types of infringement, analyzes the damage level according to the types of infringement, and calculates the maximum amount of damage and quantifies the amount of damage according to the presence or absence of information protection measures. A configured risk management processor; And generating a calculation algorithm for deriving a result by converging the data transmitted from the risk management processor, wherein the risk management server calculates the information protection level through statistical calculation according to the questionnaire result.

At this time, the damage calculation module, the protection measures selection module for selecting the information protection measures; Residual risk calculation module for analyzing the cost-effectiveness by calculating the expected risk reduction level when the information protection measures are introduced; A damage impact assessment module that analyzes the impact of damage by creating different infringement types; A damage level estimating module for analyzing the damage level according to the infringement type and calculating the maximum damage amount; And an existing result comparison module for quantifying how much damage has been reduced by comparing with when there is no information protection measure.

On the other hand, the security risk management method of the present invention, (a) to calculate the information protection level in the risk management processor in response to the data transmitted from the evaluator terminal, and to plan the detailed and detailed security risk management of the information protection level Performing a risk analysis if any; And (b) comparing the results compared with the establishment of the information protection measures, and selecting the optimal information protection measures through a feedback process based on the optimum risk reduction result.

Hereinafter, a security risk management system and method of the present invention will be described in detail with reference to the accompanying drawings.

1 is a block diagram of a security risk management system according to an embodiment of the present invention. Referring to FIG. 1, the risk management processor constituting the security risk management system of the present invention includes a high level risk analysis module 100, a low level risk analysis module 200, and a damage calculation module 300. have. A risk management server is connected to the risk management processor, and the risk management server includes a risk management engine server 400 and a questionnaire server 500, and each of them is provided with a risk analysis database and a questionnaire server database.

As described above, the existing risk analysis or risk management is largely classified into qualitative and quantitative methods. However, in the case of information and communication infrastructure, the assets are very large and the entire infrastructure is paralyzed by one attack and breach, so it is not only difficult to calculate the risk by asset but also to calculate the quantitative method in practice. impossible. Accordingly, the present invention intends to introduce a damage calculation module into the risk management processor in order to calculate the risk in a qualitative manner and to supplement the qualitative method.

The high level risk analysis module 100 calculates the level of information security through project management, status analysis, questionnaires, interviews, and control item checks. Project management estimates the scope of workforce, duration, and target facilities, and sets the level of risk analysis. Status analysis uses data collection and field visits to compare documents and records with real assets. The questionnaire analyzes the level of awareness of information security among the personnel who manage and operate the infrastructure. The interview confirms information security practices for those who are designing infrastructure and performing information security tasks. Subsequently, the control item check determines the level of information security of the organization by checking the control items based on the collected information. At this time, if the information security level is insufficient or detailed security risk management is planned, a lower level risk analysis is performed.

The lower level risk analysis module 200 calculates the level of information security through asset analysis, threat analysis, vulnerability analysis, risk calculation, report preparation, and the like. In asset analysis, information is stored on media, so assets are classified by media. Threat analysis classifies these according to the type of breach. Vulnerability analysis uses the diagnostic tools to diagnose the server and network, and then classify the results into upper and lower weights and create a classification table to calculate the level. In risk calculation, three-dimensional tables are constructed based on assets, threats, and vulnerabilities. In preparing the report, the results of the risk analysis are reported.

More specifically, vulnerability analysis generally identifies threats, but here we analyze vulnerabilities on assets. Vulnerabilities identify unnecessary services and access routes through diagnostic tools and scanners, classify the vulnerabilities into top and bottom, and classify them into top and bottom by conducting a simulated penetration test based on the discovered vulnerabilities. The exposure areas and the likelihood of penetration are also classified into 5 classes.

Risk calculations are based on threats to assets and vulnerabilities on assets, all of which add up to risk. A maximum value of 3 to 15 is expressed, and then the total risk is summed up by dividing by the number of assets after adding all the numbers. The risk value is then promulgated by calculating the value expressed as a real number from 3 to 15 as a percentage, and a report is generated based on this.

The damage estimation module 300 classifies information protection services that need to be addressed in the middle of the risk, namely confidentiality, availability, and integrity, by selecting protection measures, calculating residual risks, evaluating damage effects, calculating damage levels, and comparing existing results. Provides information security solution. In the selection of protective measures, the protective measures are selected. The residual risk calculation analyzes the cost-effectiveness by estimating the expected level of risk reduction when an information security solution is introduced. The impact assessment analyzes the impact of damage by creating different types of infringement. In the damage level estimation, the damage level according to the type of infringement is analyzed and the maximum damage amount is calculated. The comparison of existing results quantifies how much damage has been reduced by comparing with and without protection.

On the other hand, for each of the upper level risk analysis module 100, the lower level risk analysis module 200, the damage calculation module 300, it is preferable to modularize each function.

A series of all the details of the risk management processor are made in the client, which is the evaluator terminal 601, and the result is stored in the risk management engine server 400 of the risk management server through the network. The risk management engine server 400 provides a list of assets, threats, vulnerabilities, and protection measures to the risk management processor, and the evaluators perform the evaluation task based on the list. In addition, all the results performed by the evaluator are arranged by the evaluator using the evaluator terminal 600 to create an optimal analysis result.

Here, the functions of the risk management engine 400 and the questionnaire server 500 constituting the risk management server will be described in detail. The risk management engine server 400 collects opinions based on the results entered by the evaluators. It generates an algorithm that calculates to provide a single result, the questionnaire server 500, the facility operator and facility managers statistically about the results of the questionnaire entered through the facility operator terminal 603 and facility manager terminal 602 Calculate the level of information security. Each result is databased in a risk analysis database and a survey server database respectively. On the other hand, the risk management engine server allows each evaluator to refer to the results entered by each evaluator so that they can collect their own opinions. Based on the results finally collected, the evaluator decides the results. In each process, when the evaluator decides the result, the next process can proceed.

At this time, the risk analysis database is composed of asset list database 401, threat list database 402, vulnerability list database 403, safeguard list database 404, among them, the threat list is input data related to damage calculation To utilize. Threats are classified into viruses, worms, hacking, and damages caused by unintentional actions, and the threat list is defined by selecting detailed items for each item. To this end, a list is composed of several items, and a list of threats is selected and provided for the asset. This is because a large list of threats presents confusion to the evaluator if it is viewed in full for an individual asset. For example, in the case of a Windows system, it shows only threats associated with Windows. If a threat is selected for the asset, the threat level is calculated by classifying it into 5 grades.

On the other hand, the biggest problem with current security risk management systems is that the evaluator cannot identify the exact value of the information asset. In order to solve this problem, it is necessary to evaluate the level of media that has information assets. In case of important information, it will be stored and managed in a good system and a high speed network system will be used for transmission and reception. In the case of lower grade information, it will be stored in some drawers, while on paper or diskette. Therefore, when the level of media is assessed and graded, accurate asset analysis is performed, and information security solutions for the media can be easily implemented by analyzing threats and vulnerabilities of the media. Here, the medium refers to a device that people can see and read, such as paper, safes, and hardware, and includes mail, telephone, and the Internet according to transmission. The media that manages this important information are classified into confidentiality, integrity, and availability, and the grades are divided into five grades, and a three-dimensional table is formed to determine the final grade. In this case, each evaluator should be provided with the basic data necessary to calculate the grade. These data are obtained from the risk management engine server, which is stored based on the results from the higher level risk analysis module. The results obtained can refer to the results entered by other evaluators and allow them to compare and correct their results. It is possible to revise the result value for a certain period of time, and if the evaluator decides the evaluation result after a certain time, it is no longer possible to modify it.

So far, the qualitative method has been described. The qualitative method allows managers to see how much information is protected by the institutions they manage, but it does not know how much damage is done when an infringement occurs. In order to solve this limitation of risk management, quantitative methods are used.In the case of information and communication infrastructure, since the assets are very large and interlocked, many people and time are invested in asset identification and asset value estimation. Will also fall a lot. In order to solve this problem, the present invention intends to include a process for checking how much damage has occurred through a risk calculation processor and selecting a protection measure and checking how the risk has been reduced.

In the case of safeguards selection, the appropriate countermeasures should be checked and analyzed for possible response to threats. It then determines what residual risk is and decides whether to accept, avoid or accept it. This decision should be made by evaluating the impact of damage and estimating the level of damage and comparing it with when there is no protection.

Through this security risk management system, it is possible to secure the safety of information and communication infrastructure and to provide certain rules and procedures to the managers and operators who manage the facilities.

2 is a damage calculation graph according to an embodiment of the present invention. Referring to FIG. 2, when a failure occurs in an information and communication infrastructure, a total damage amount is calculated by multiplying a time loss cost of a user and an administrator operating a facility from a failure occurrence to a termination point. However, in the present invention, since all systems are not interrupted at one time, comprehensively analyzing the logs of the network management system and the server and calculating the total by arranging facilities that do not perform services due to failure or failure of each asset by time. Therefore, after calculating the area value for the curve, it is possible to obtain the net damage amount compared to the total damage amount. The damage calculation formula is as follows.

Damage =

Where A is the maximum loss cost per hour, and B is the time, respectively.

3 is a table showing the total asset information for the information communication infrastructure according to an embodiment of the present invention. As shown in FIG. 3, information on all assets of the information and communication infrastructure is stored in an asset list, and a connection state between the assets is databased.

4 is a security risk analysis diagram according to an embodiment of the present invention. As shown in FIG. 4, the analysis of which assets are affected in the facility through the infringement obtained from the threat list and the vulnerability list is expressed, and the protection measures are expressed. Currently, infrastructure can be classified into confidentiality, integrity and availability, and once the risks are calculated, the risks can be reduced by using information protection solutions such as prevention, monitoring and recovery. This will be described in detail with reference to FIG. 12.

5 is a process screen of the risk management processor according to an embodiment of the present invention. Referring to FIG. 5, as the tooling and automation of the risk management processor are possible, the evaluators can adjust the evaluation result while viewing and entering information remotely.

6 is a questionnaire server screen of the security risk management system according to an embodiment of the present invention. Referring to FIG. 6, a tool implemented as a content of a questionnaire server is composed of a web environment, and facility managers and operators input information security levels they feel through a questionnaire. The questionnaire server stores the results collectively in a professional database (501 of FIG. 1) and a general database (502 of FIG. 1). Then, this result is calculated as a score by the weight and grade calculation method in the risk management engine server.

Example

In this embodiment, the process of the low-level risk analysis module consisting of asset analysis, threat analysis, vulnerability analysis, risk calculation, and risk analysis diagram will be described in detail, followed by damage calculation analysis that forms the central idea of the present invention. .

First of all, the asset classification and the following information security requirements, importance and sensitivity analysis are described.

The present invention proposes a method for identifying and evaluating the information and communication infrastructure rather than the asset classification of the entire asset of the organization, and thus classifies the information and communication infrastructure as follows.

Server: Hardware, OS and basic services such as server, PC, network equipment

Application: Application that supports the organization's goals and tasks

Data: Information and data to carry out organizational goals and tasks

On the other hand, in order to analyze the information security requirements of assets in all standards or risk analysis methodologies, three factors such as confidentiality, integrity and availability are evaluated. It proposes a method for identifying and evaluating ICT infrastructure, rather than classifying the entire asset of an organization. The criticality of an information and communication infrastructure expresses values in terms of confidentiality, integrity and availability, and the sensitivity of the data is reflected in calculating confidentiality values.

[Table 1] Classification of information security elements of information and communication infrastructure

Sensitivity is not included in other information security elements but only data. Therefore, data sensitivity is analyzed and the value is rated as shown in [Table 2].

Table 2 Data Sensitivity

7A to 7C are maps for analyzing importance of data, an application, and a server according to an embodiment of the present invention.

7A to 7C, V values of data are expressed as Vector values of C, I, and A, V values of applications are Vector values of I and A, and S values of servers are represented as Scalar values of A. Data and applications record the order of what information security requirements are required in addition to the V value.

=(C1, I1, A1), 데이터 2 :

= (I2, C2, A2) Data 1:

= (C1, I1, A1), data 2:

= (I2, C2, A2)

= (A1, I1), 어플리케이션 2 :

= (I2, A2)Application 1:

= (A1, I1), application 2:

= (I2, A2)

Server 1: S1 = A1, Server 2: S2 = A2

에서부터

의 결과를 갖는다. 역시, [표 4]와 같이 어플리케이션은

에서부터

의 결과를 얻을 수 있다. 서버의 경우에는 [표 5]와 같이 1에서부터 9의 값을 가지게 되며 각각의 값들을 3가지로 등급화하고 이에 대한 기준의 정의한다. Table 3 shows the results of grading the importance of the data. Calculating values for availability, integrity, and confidentiality

From

Has the result. Again, the application as shown in Table 4

From

Results in: In the case of the server, as shown in [Table 5], it has a value of 1 to 9, and each value is graded in three and defines the criteria for this.

[Table 3] Criticality grading of data

[Table 4] Criticality grading of applications

[Table 5] Criticality of Servers

8 is a map for identifying a connection configuration of a server, an application, and data according to an embodiment of the present invention.

In order to understand the connection configuration of the server, application, and data, a mapping configuration is performed as shown in FIG. 8.

= (SV1, AP1, DT1)Mapping 1:

= (SV1, AP1, DT1)

= (SV1, AP2, DT2)Mapping 2:

= (SV1, AP2, DT2)

= (SV2, AP3, DT3) Mapping 3:

= (SV2, AP3, DT3)

= (SV3, AP4)Mapping 4:

= (SV3, AP4)

For each mapping, the classification and evaluation are performed by calculating Vector and Scalar values, which are criticality values.

9A to 9D are maps for analyzing importance of mapped data, applications, and servers according to an embodiment of the present invention.

,

,

값은 DT, AP, SV의 Vector 값, 매핑 4의

은 AP, SV의 Vector 값으로 표현된다. [표 6]은 3차원 매핑에 대한 등급이며, [표 7]은 2차원 매핑, 그리고 [표 8]은 1차원 매핑에 대한 등급을 표시한다. 9A to 9D, mappings 1 and 2

,

,

The values are the vector values of DT, AP, SV, and mapping 4.

Is expressed as a Vector value of AP and SV. Table 6 shows the ratings for the three-dimensional mapping, Table 7 shows the two-dimensional mapping, and Table 8 shows the ratings for the one-dimensional mapping.

[Table 6] Severity ratings of configurations to which data, applications and servers are mapped

[Table 7] Severity ranking of mapped configuration such as data and server

[Table 8] Importance values for each data, application and server

The priorities of these information security requirements are illustrated in Figure 4, and the importance levels are classified into three levels: high (red), medium (yellow), and low (green). In other words, High (Red) can be classified as a major asset of the organization, and in some cases, Medium (Yellow) can be classified as a risk analysis asset. Internally, it expresses the priority of which information security requirements are more important.

FIG. 10 is a table illustrating criticality of data, applications, and servers according to an embodiment of the present invention.

Next, the threat analysis will be described.

In the threat analysis proposed in the present invention, when the threat agent is a human (hacker, user, developer, system administrator), the security strength calculation rule of ITSEM (European Evaluation Standard) is extended to five levels, and the non-human (natural disaster, In the case of failure, etc., five criteria by frequency of occurrence were used. In ITSEM, the concept of “security intensity” of information systems is the opposite of “threat level”. It is assumed that the higher the security strength, the lower the threat level and the threat concept includes the “attack” concept. That is, the threat level is determined as a function of attack time, collusion, threat expertise, and the level of attack equipment available to the threat agent. CSE and OCTAVE also consider the threat agents' motives and capabilities, but are less specific than this method. To make it easier to identify asset-specific threats, PKB provides a threat database that expands the threat statements used in the Protection Profile (PP). First, the threat list of the PKB, the threat database of CC, was referred and expanded, and the threat agents were classified as the primary criteria and the threat behaviors and the target assets were classified as the secondary and tertiary criteria. Threats used in the actual PP and additionally found threats during evaluation can be added to the class or component. Each threat agent is classified into human and non-human. In the case of humans, we mean the "system administrator", the "malicious and unauthorized individual", the "system / evaluation product developer" and the "authorized user" classes. In the case of nonhumans, we mean the classes 'physical environment', 'system / HW / SW' and 'natural disaster'. [Table 9] to [Table 16] are table matrices for threat analysis.

TABLE 9 T1. Attack time

TABLE 10 T2. Open call

TABLE 11 T3. Attack Time-Complicity

TABLE 12 T4. professionalism

TABLE 13 T5. Attack equipment

TABLE 14 T6. Expertise-Attack Equipment

TABLE 15 T7. Human threat level

TABLE 16 T8. Non-human threat level

Next, the vulnerability analysis will be described.

Because vulnerabilities are defined as "system properties on which asset-specific threats can be realized," the classification of vulnerabilities is identical to that of threats. Vulnerability sentences can be added to the threat statement with the word "vulnerability to". For example, the vulnerability to the threat "T1.1.1 accidental management error of cryptographic functions" can be interpreted as "vulnerability to accidental management error of cryptographic functions". Since the vulnerability level is defined as “the extent to which asset-specific threats can be realized,” there is no need to identify vulnerabilities, but it is necessary to rank the extent to which asset-specific threats can be realized.

TABLE 17 V1. Vulnerability exposure

TABLE 18 V2. Severity of the Vulnerability

TABLE 19 V3. Vulnerability level

TABLE 20 V4. Interpretation of vulnerability levels (interpretation of V3)

Next, the risk calculation is explained.

The risk calculation calculates the risk level for the entire ICT infrastructure based on the results analyzed so far. The calculation algorithm is shown in Table 21.

Table 21.Calculation of risk-related measures

Risk analysis, on the other hand, should not be completed at one time, but should be able to be analyzed in a timely manner as assets, threats, and vulnerabilities change from time to time. The following cases are assumed to calculate the risk due to time-varying threats / vulnerabilities:

(precondition)

■ Threats / vulnerabilities occur at regular intervals.

■ Newly discovered threats / vulnerabilities differ from previous threats / vulnerabilities.

■ If a protective measure is established against the threats / vulnerabilities found, the risks no longer increase due to the threats / vulnerabilities.

If threats / vulnerabilities continue to occur periodically for the ICT infrastructure, the corresponding risks increase. These risks are either reduced by countermeasures or prevented further increases in risk. This state is expressed as shown in FIG.

As shown in FIG. 11, if threats / vulnerabilities continue to occur over time, the risk increases as P. FIG. Here, risk is divided into five grades. Countermeasures are considered when the threat is level 3 or higher, and through countermeasures the risk is reduced to Q. Since countermeasures occur after a period of time after threats / vulnerabilities, it is very important to establish timely countermeasures so that risks do not continue to increase. The reduced effect corresponds to the area indicated by the difference between P and Q. The block diagram for the time-varying risk analysis can be expressed as shown in FIG.

G (k): network system (confidentiality, integrity, availability)

   G (C, I, A) = {1, 2, 3, 4, 5}

S (k): Information protection system (prevention, detection, recovery)

   S (D, P, R) = {1, 2, 3, 4, 5}

R (k), y (k): Risk rate, r (k) = {1, 2, 3, 4, 5}

E (k): failure, exploit, e (k) = {1, 2, 3, 4, 5}

T: Threat, t = {0, 1}

V: vulnerability, v = {0, 1}

K: time

The risk formula for cyber attack in the above system is as follows.

■

■

■

■

■

: 보수■

: repair

■

은 3차원 테이블 매트릭스이다. here,

Is a three-dimensional table matrix.

On the other hand, the processing in the damage estimation module which is one of the important technical idea of the present invention will be described in detail.

In the past, failure management for failure management and malfunction caused by software bugs were the main issues for system availability. Recently, however, a management method for protecting a system and providing a real-time service has been given priority. However, security management organizations and personnel do not respond appropriately in real time. In the case of conventional failure handling, it was solved by replacing or re-starting the asset, but cyber infringement incidents should eliminate the source of the threat and prevent further damage. In the event of an infringement of a single asset, the asset's status is When one intrusion occurs, the unit asset for it is incurred a load after the intrusion occurs, and this load gradually brings the service to failure and eventually causes the system to stop. 13 shows a state for this, and the damage may be configured in various types of functions.

When programming the characteristics of a unit asset, it is expressed as Includes the type of asset, the type of intrusion, security patches, upgrades, and service pack handling.

 class Result Asset (int I_category, class A_type) R.delay = t_i, R.interrupt = t_i + tau; A.Security.Service = parameter; A.Security.Update = level; Case Virus: R.wave = Linear_fn (); Case Worm: R.wave = exponential_fn (); Case Hacking: R.wave = Pulse_fn (); Case Mistake: R.wave = Log_fn ();

The damages resulting from the breach of the ICT infrastructure can be calculated from the sum of these unit assets. When a cyber attack occurs on the infrastructure, unit assets lose their function in a chain, and the spreading speed and spread range according to the result are shown in FIG. 14.

The function f (t) for damage occurrence and the function g (t) for damage recovery are expressed in the same coordinates, and the total damage estimate (R) is the sum of the total costs incurred during the breach and the total costs incurred during the recovery. It is represented by the sum.

At this time, the damage calculation (A) when the system load occurs, including the management cost and operation costs, the damage calculation (B) when the system failure occurs, including the management cost, operation cost to the service loss cost. In order to distinguish from the cost of damage, the cost of protection measures include control and early warning costs, which are classified into costs for prevention, detection, and recovery. Prevention costs are the costs of preventing intrusions into the ICT infrastructure, detection costs are the costs of detecting intrusions, and recovery costs are the costs of recovering from damage.

Although the present invention has been described in more detail with reference to some embodiments, the present invention is not necessarily limited to these embodiments, and various modifications can be made without departing from the spirit of the present invention.

As described above, the security risk management system and method according to the present invention has the following effects.

First, objective evidence can be provided for the selection of protective measures by providing the results of estimating the impact and level of damage in addition to the qualitative assessment.

Second, evaluators can reduce the range of error by obtaining various information necessary for evaluation online and comparing the results.

Third, since the results are stored in the risk management engine server, it is easy to analyze various infringements, and the difference in evaluation results can be minimized because the history and fairness of the evaluation are provided.

Fourth, since the spread and level of damage can be estimated in the evaluation, it is possible to lay the foundation for establishing immediate protection measures in the risk analysis process and easily perform reanalysis based on the established results.

Claims (13)

High-level risk analysis module that calculates information security level in response to data transmitted from evaluator's terminal, and low-level risk analysis that performs risk analysis when planning detailed security risk management and detailed information security level. The module and the protected object are classified into confidentiality, integrity, and availability to provide the corresponding information protection measures, but the cost-effectiveness analysis and various types of infringement are made by calculating the expected level of risk reduction when the information protection measures are introduced. A risk management processor comprising a damage estimation module that analyzes the damage effect, the damage level according to the infringement type, calculates the maximum damage amount, and quantifies the damage amount according to the presence or absence of information protection measures; And A risk management server that generates a calculation algorithm that derives a result by converging data transmitted from the risk management processor, and calculates a level of information protection through statistical calculation according to a questionnaire result. Security risk management system comprising a. The method of claim 1, wherein the damage calculation module, A protection measure selection module for selecting the information protection measure; Residual risk calculation module for analyzing the cost-effectiveness by calculating the expected risk reduction level when the information protection measures are introduced; A damage impact assessment module that analyzes the impact of damage by creating different infringement types; A damage level estimating module for analyzing the damage level according to the infringement type and calculating the maximum damage amount; And Existing result comparison module to quantify how much damage is reduced by comparing with when there is no information protection measures Security risk management system, characterized in that consisting of. The method of claim 1, wherein the risk management server, It includes a risk analysis database consisting of an asset list database, threat list database, vulnerability list database, and countermeasure list database, and provides a list of assets, threats, vulnerabilities, and countermeasures as a risk management processor. A risk management engine server for generating a calculation algorithm that collects opinions based on the processed data and generates a result; And It includes a questionnaire server database consisting of a professional database and a general purpose database, and a questionnaire server that calculates the level of information security by statistically calculating the results of the survey entered by the facility operator and facility manager through the facility operator terminal and facility manager terminal. Security risk management system, characterized in that consisting of. The method of claim 1, wherein the high level risk analysis module, A project management module for estimating the scope of the workforce, duration, target facility and level of risk analysis; A status analysis module that compares documents and records with real assets through data collection and field visits; Questionnaire module for analyzing the information security awareness level for the personnel who manage and operate the target facility; An interview module for identifying information protection status for those who design the target facility and perform information security tasks; And Control item check module that checks the control items based on the collected information and calculates the level of information security of the organization Security risk management system, characterized in that consisting of. The method of claim 1, wherein the low-level risk analysis module, An asset analysis module for classifying assets in a medium because information is stored in the medium; A threat analysis module for classifying the infringement type; A vulnerability analysis module for classifying the results of the server and network after using the diagnostic tool into heavy weights and creating a classification table to calculate the level; A risk calculation module for constructing and calculating a three-dimensional table based on assets, threats, and vulnerabilities; And Report module to report results Security risk management system, characterized in that consisting of. (a) estimating the level of information protection in the risk management processor in response to the data transmitted from the evaluator's terminal, and performing risk analysis when planning the level of detail and detailed security risk management; (b) selecting the optimal information protection measures through a feedback process based on the results of the optimal risk reduction by comparing the results compared with the establishment of the information protection measures; Security risk management method comprising a. The method of claim 6, wherein steps (a) and (b) provide a list of assets, threats, vulnerabilities, and countermeasures to the risk management processor, and based on the data processed by the risk management processor at the evaluator's terminal. A risk management server that calculates the level of information protection by statistically calculating the results of the surveys entered by the facility operator and the facility manager terminal through the facility operator terminal and the facility administrator terminal Security risk management method characterized in that performed through the linkage. The method of claim 6, wherein the step (b) comprises: selecting the information protection measures, analyzing the cost-effectiveness by calculating the expected level of risk reduction when the information protection measures are introduced, and various types of infringement. The process of analyzing the impact of damage by analyzing the damage, analyzing the damage level according to the type of infringement, calculating the maximum damage amount, and quantifying how much the damage was reduced by comparing it with the absence of the above information protection measures. Security risk management method characterized in that. 7. The method of claim 6, wherein the optimal information protection measure is selected through the evaluator terminal in step (b). The method of claim 6, wherein the step of estimating the level of information security in step (a) comprises the steps of estimating the scope of manpower, period, target facility, level of risk analysis, data collection and field inspection. The process of comparing the records with actual assets, analyzing the level of awareness of information security for the people who manage and operate the target facilities, and the information protection status for those who design the target facilities and perform information security tasks. Security risk management method comprising the step of checking the information and the control items based on the collected information to determine the level of information security of the organization. The method of claim 6, wherein the performing of the risk analysis of step (a) comprises: (a-1) classifying an asset for a medium storing information, and (a-2) classifying an infringement type. (a-3) The process of diagnosing servers and networks using diagnostic tools to classify the results from top to bottom, creating a classification table, and estimating the level. (a-4) Based on assets, threats, and vulnerabilities 3 Security risk management method comprising the steps of constructing and calculating the dimensional table and (a-5) reporting the results. 12. The method of claim 11, wherein in the step (a-1), the server is an hardware, an OS, and a basic service such as a server, a PC, and a network device, and an application program that supports an organization's goals and tasks. A security risk management method characterized by classification into data, information and data for performing applications, organizational goals and tasks. 12. The method of claim 11, wherein the criticality of the information and communication infrastructure is expressed in terms of confidentiality, integrity, and availability in the process (a-3).

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