Doc:NIST SP 800-53Ar1 FPD Chapter 1
THE NEED TO ASSESS SECURITY CONTROL EFFECTIVENESS IN INFORMATION SYSTEMS
Today's information systems are complex assemblages of technology (i.e., hardware, software, and firmware), processes, and people, working together to provide organizations with the capability to process, store, and transmit information in a timely manner to support various missions and business functions. The degree to which organizations have come to depend upon these information systems to conduct routine, important, and critical missions and business functions means that the protection of the underlying systems is paramount to the success of the organization. The selection of appropriate security controls for an information system is an important task that can have major implications on the operations and assets of an organization as well as the welfare of individuals. Security controls are the management, operational, and technical safeguards or countermeasures prescribed for an information system to protect the confidentiality, integrity (including non-repudiation and authenticity), and availability of the system and its information. Once employed within an information system, security controls are assessed to provide the information necessary to determine their overall effectiveness; that is, the extent to which the controls are implemented correctly, operating as intended, and producing the desired outcome with respect to meeting the security requirements for the system. Understanding the overall effectiveness of the security controls implemented in the information system and its environment of operation is essential in determining the risk to the organization's operations and assets, to individuals, to other organizations, and to the Nation resulting from the use of the system.
1.1 PURPOSE AND APPLICABILITY
The purpose of this publication is to provide guidelines for building effective security assessment plans and a comprehensive set of procedures for assessing the effectiveness of security controls employed in information systems supporting the executive agencies of the federal government. The guidelines apply to the security controls defined in Special Publication 800-53 (as amended), Recommended Security Controls for Federal Information Systems and Organizations. The guidelines have been developed to help achieve more secure information systems within the federal government by:
- Enabling more consistent, comparable, and repeatable assessments of security controls;
- Facilitating more cost-effective assessments of security controls contributing to the determination of overall control effectiveness;
- Promoting a better understanding of the risks to organizational operations, organizational assets, individuals, other organizations, and the Nation resulting from the operation and use of federal information systems; and
- Creating more complete, reliable, and trustworthy information for organizational officials to support risk management decisions, reciprocity of assessment results, information sharing, and FISMA compliance.
This publication satisfies the requirements of the Federal Information Security Management Act (FISMA) and meets or exceeds the information security requirements established for executive agencies by the Office of Management and Budget (OMB) in Circular A-130, Appendix III, Security of Federal Automated Information Resources. The guidelines in this publication are applicable to all federal information systems other than those systems designated as national security systems as defined in 44 U.S.C., Section 3542. The guidelines have been broadly developed from a technical perspective to complement similar guidelines for national security systems and may be used for such systems with the approval of appropriate federal officials exercising policy authority over such systems. State, local, and tribal governments, as well as private sector organizations are encouraged to consider using these guidelines, as appropriate.
Organizations use this publication in conjunction with an approved security plan in developing a viable security assessment plan for producing and compiling the information necessary to determine the effectiveness of the security controls employed in the information system. This publication has been developed with the intention of enabling organizations to tailor and supplement the basic assessment procedures provided. The assessment procedures are used as a starting point for and as input to the security assessment plan. In developing effective security assessment plans, organizations take into consideration existing information about the security controls to be assessed (e.g., results from organizational assessments of risk, platform-specific dependencies in the hardware, software, or firmware, and any assessment procedures needed as a result of organization-specific controls not included in Special Publication 800-53).
- The security categorization of the information system;
- The assurance requirements that the organization intends to meet in determining the overall effectiveness of the security controls; and
- The selection of security controls from Special Publication 800-53 as identified in the approved security plan.
The assessment process is an information-gathering activity, not a security-producing activity. Organizations determine the most cost-effective implementation of this key element in the organization's information security program by applying the results of risk assessments, considering the maturity and quality level of the organization's risk management processes, and taking advantage of the flexibility in the concepts described in this publication. The use of Special Publication 800-53A as a starting point in the process of defining procedures for assessing the security controls in information systems and organizations, promotes a consistent level of security and offers the needed flexibility to customize the assessment based on organizational policies and requirements, known threat and vulnerability information, operational considerations, information system and platform dependencies, and tolerance for risk. The information produced during security control assessments can be used by an organization to:
- Identify potential problems or shortfalls in the organization's implementation of the Risk Management Framework;
- Identify information system weaknesses and deficiencies;
- Prioritize risk mitigation decisions and associated risk mitigation activities;
- Confirm that identified weaknesses and deficiencies in the information system have been addressed;
- Support continuous monitoring activities and information security situational awareness;
- Facilitate security authorization decisions; and
- Inform budgetary decisions and the capital investment process.
Organizations are not expected to employ all of the assessment methods and assessment objects contained within the assessment procedures identified in this publication for the associated security controls deployed within or inherited by organizational information systems. Rather, organizations have the inherent flexibility to determine the level of effort needed for a particular assessment (e.g., which assessment methods and assessment objects are deemed to be the most useful in obtaining the desired results). This determination is made on the basis of what will accomplish the assessment objectives in the most cost-effective manner and with sufficient confidence to support the subsequent determination of the resulting mission or business risk.
1.2 TARGET AUDIENCE
This publication is intended to serve a diverse group of information system and information security professionals including:
- Individuals with information system development and integration responsibilities (e.g., program managers, information technology product developers, information system developers, systems integrators, information security architects);
- Individuals with information security assessment and continuous monitoring responsibilities (e.g., system evaluators/testers, penetration testers, security control assessors, independent verifiers and validators, auditors, information system owners, common control providers);
- Individuals with information system and security management and oversight responsibilities (e.g., authorizing officials, senior information security officers, information security managers); and
- Individuals with information security implementation and operational responsibilities (e.g., information system owners, common control providers, information owners/stewards, mission owners, systems administrators, information system security officers).
1.3 RELATED PUBLICATIONS AND ASSESSMENT PROCESSES
Special Publication 800-53A is designed to support Special Publication 800-37, Guide for Applying the Risk Management Framework to Federal Information Systems: A Security Life Cycle Approach. In particular, the assessment procedures contained in this publication and the guidelines provided for developing security assessment plans for organizational information systems directly support the security control assessment and continuous monitoring activities that are integral to the risk management process. This includes providing near real-time information to organizational officials regarding the ongoing security state of their information systems.
Organizations are encouraged, whenever possible, to take advantage of the assessment results and associated assessment-related documentation and evidence available on information system components from previous assessments including independent third-party testing, evaluation, and validation. Product testing, evaluation, and validation may be conducted on cryptographic modules and general-purpose information technology products such as operating systems, database systems, firewalls, intrusion detection devices, Web browsers, Web applications, smart cards, biometrics devices, personal identity verification devices, network devices, and hardware platforms using national and international standards. If an information system component product is identified as providing support for the implementation of a particular security control in Special Publication 800-53, then any available evidence produced during the product testing, evaluation, and validation processes (e.g., security specifications, analyses and test results, validation reports, and validation certificates) is used to the extent that it is applicable. This evidence is combined with the assessment-related evidence obtained from the application of the assessment procedures in this publication, to cost-effectively produce the information necessary to determine whether the security controls are effective in their application.
1.4 ORGANIZATION OF THIS SPECIAL PUBLICATION
The remainder of this special publication is organized as follows:
- Chapter Two describes the fundamental concepts associated with security control assessments including: (i) the integration of assessments into the system development life cycle; (ii) the importance of an organization-wide strategy for conducting security control assessments; (iii) the development of effective assurance cases to help increase the grounds for confidence in the effectiveness of the security controls being assessed; and (iv) the format and content of assessment procedures.
- Chapter Three describes the process of assessing the security controls in organizational information systems and their environments of operation including: (i) the activities carried out by organizations and assessors to prepare for security control assessments; (ii) the development of security assessment plans; (iii) the conduct of security control assessments and the analysis, documentation, and reporting of assessment results; and (iv) the post-assessment report analysis and follow-on activities carried out by organizations.
- Supporting appendices provide detailed assessment-related information including: (i) general references; (ii) definitions and terms; (iii) acronyms; (iv) a description of assessment methods; (v) penetration testing guidelines; (vi) a master catalog of assessment procedures that can be used to develop plans for assessing security controls; (vii) content of security assessment reports; and (viii) the definition, format, and use of assessment cases.
- 9 An information system is a discrete set of information resources organized expressly for the collection, processing, maintenance, use, sharing, dissemination, or disposition of information.
- 10 When selecting security controls for an information system, the organization also considers potential impacts to other organizations and, in accordance with the USA PATRIOT Act of 2001 and Homeland Security Presidential Directives, potential national-level impacts.
- 11 An executive agency is: (i) an executive department specified in 5 U.S.C., Section 101; (ii) a military department specified in 5 U.S.C., Section 102; (iii) an independent establishment as defined in 5 U.S.C., Section 104(1); and (iv) a wholly owned government corporation fully subject to the provisions of 31 U.S.C., Chapter 91. In this publication, the term executive agency is synonymous with the term federal agency.
- 12 In accordance with the provisions of FISMA and OMB policy, whenever the interconnection of federal information systems to information systems operated by state/local/tribal governments, contractors, or grantees involves the processing, storage, or transmission of federal information, the information security standards and guidelines described in this publication apply. Specific information security requirements and the terms and conditions of the system interconnections, are expressed in the Memorandums of Understanding and Interconnection Security Agreements established by participating organizations.
- 13 For example, detailed test scripts may need to be developed for the specific operating system, network component, middleware, or application employed within the information system to adequately assess certain characteristics of a particular security control. Such test scripts are at a lower level of detail than provided by the assessment procedures contained in Appendix F (Assessment Procedures Catalog) and are therefore beyond the scope of this publication. Additional details for assessments are provided in the supporting assessment cases described in Appendix H.
- 14 For national security systems, security categorization is accomplished in accordance with CNSS Instruction 1253. For other than national security systems, security categorization is accomplished in accordance with FIPS 199 and Special Publication 800-60.
- 15 The agreed-upon security controls for the information system are documented in the security plan after the initial selection of the controls as described in Special Publication 800-53. The security plan is approved by appropriate organizational officials prior to the start of the security control assessment.
- 16 In this publication, the term risk is used to mean risk to organizational operations (i.e., mission, functions, image, and reputation), organizational assets, individuals, other organizations, and the Nation.
- 17 At the agency level, this position is known as the Senior Agency Information Security Officer. Organizations may also refer to this position as the Chief Information Security Officer.
- 18 Assessment results can be obtained from many activities that occur routinely during the system development life cycle. For example, assessment results are produced during the testing and evaluation of new information system components during system upgrades or system integration activities. Organizations can take advantage of previous assessment results whenever possible, to reduce the overall cost of assessments and to make the assessment process more efficient.
- 19 Organizations review the available information from component information technology products to determine: (i) what security controls are implemented by the product; (ii) if those security controls meet the intended control requirements of the information system under assessment; (iii) if the configuration of the product and the environment in which the product operates are consistent with the environmental and product configuration stated by the vendor and/or developer; and (iv) if the assurance requirements stated in the developer/vendor specification satisfy the assurance requirements for assessing those controls. Meeting the above criteria provides a sound rationale that the product is suitable and meets the intended security control requirements of the information system under assessment.