(ISC)2 CISSP Certified Information Systems Security Professional Official Study Guide. Mike Chapple

(ISC)2 CISSP Certified Information Systems Security Professional Official Study Guide - Mike Chapple


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it can be adopted and adapted by other types of organization as well. Many organizations adopt security frameworks in an effort to standardize and organize what can become a complex and bewilderingly messy activity, namely, attempting to implement reasonable security governance.

      Third-Party Governance

      Third-party governance is the system of external entity oversight that may be mandated by law, regulation, industry standards, contractual obligation, or licensing requirements. The actual method of governance may vary, but it generally involves an outside investigator or auditor. These auditors might be designated by a governing body or might be consultants hired by the target organization.

      Another aspect of third-party governance is the application of security oversight to third parties that your organization relies on. Many organizations choose to outsource various aspects of their business operations. Outsourced operations can include security guards, maintenance, technical support, and accounting services. These parties need to stay in compliance with the primary organization's security stance. Otherwise, they present additional risks and vulnerabilities to the primary organization.

      Third-party governance focuses on verifying compliance with stated security objectives, requirements, regulations, and contractual obligations. On-site assessments can provide firsthand exposure to the security mechanisms employed at a location. Those performing on-site assessment or audits need to follow auditing protocols (such as Control Objectives for Information and Related Technology [COBIT]) and have a specific checklist of requirements to investigate.

      In the auditing and assessment process, both the target and the governing body should participate in full and open document exchange and review. An organization needs to know the full details of all requirements it must comply with. The organization should submit security policy and self-assessment reports back to the governing body. This open document exchange ensures that all parties involved are in agreement about all the issues of concern. It reduces the chances of unknown requirements or unrealistic expectations. Document exchange does not end with the transmission of paperwork or electronic files. Instead, it leads into the process of documentation review.

      See Chapter 12, “Secure Communications and Network Attacks,” for a discussion of third-party connectivity.

      Documentation Review

      In many situations, especially related to government or military agencies or contractors, failing to provide sufficient documentation to meet requirements of third-party governance can result in a loss of or a voiding of authorization to operate (ATO). Complete and sufficient documentation can often maintain existing ATO or provide a temporary ATO (TATO). However, once an ATO is lost or revoked, a complete documentation review and on-site review showing full compliance is usually necessary to reestablish the ATO.

      A portion of the documentation review is the logical and practical investigation of the business processes and organizational policies in light of standards, frameworks, and contractual obligations. This review ensures that the stated and implemented business tasks, systems, and methodologies are practical, efficient, and cost-effective, and most of all (at least in relation to security governance) that they support the goal of security through the reduction of vulnerabilities and the avoidance, reduction, or mitigation of risk. Risk management, risk assessment, and addressing risk are all methods and techniques involved in performing process/policy review.

      The security function is the aspect of operating a business that focuses on the task of evaluating and improving security over time. To manage the security function, an organization must implement proper and sufficient security governance.

      The act of performing a risk assessment to drive the security policy is the clearest and most direct example of management of the security function. The process of risk assessment is discussed in Chapter 2.

      Security must be measurable. Measurable security means that the various aspects of the security mechanisms function, provide a clear benefit, and have one or more metrics that can be recorded and analyzed. Similar to performance metrics, security metrics are measurements of performance, function, operation, action, and so on as related to the operation of a security feature. When a countermeasure or safeguard is implemented, security metrics should show a reduction in unwanted occurrences or an increase in the detection of attempts. The act of measuring and evaluating security metrics is the practice of assessing the completeness and effectiveness of the security program. This should also include measuring it against common security guidelines and tracking the success of its controls. Tracking and assessing security metrics is part of effective security governance.

      Managing the security function includes the development and implementation of information security strategies. Most of the content of the CISSP exam, and hence this book, addresses the various aspects of development and implementation of information security strategies.

      Alignment of Security Function to Business Strategy, Goals, Mission, and Objectives

      One of the most effective ways to tackle security management planning is to use a top-down approach. Upper, or senior, management is responsible for initiating and defining policies for the organization. Security policies provide direction for all levels of the organization's hierarchy. It is the responsibility of middle management to flesh out the security policy into standards, baselines, guidelines, and procedures. The operational managers or security professionals must then implement the configurations prescribed in the security management documentation. Finally, the end users must comply with all the security policies of the organization.

      

The opposite of the top-down approach is the bottom-up approach. In a bottom-up approach environment, the IT staff makes security decisions directly without input from senior management. The bottom-up approach is rarely used in organizations and is considered problematic in the IT industry.


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