[ISN] ITL Bulletin for May 2005

InfoSec News isn at c4i.org
Tue May 24 04:56:00 EDT 2005

Forwarded from: Elizabeth Lennon <elizabeth.lennon at nist.gov>



Shirley Radack, Editor
Computer Security Division
Information Technology Laboratory
National Institute of Standards and Technology
Technology Administration
U.S. Department of Commerce

Security controls are the management, operational, and technical
safeguards that protect the confidentiality, integrity, and
availability of an information system and its information.
Organizations face critical decisions in selecting and implementing
the right controls and in making the controls an effective part of
their information security programs. The Information Technology
Laboratory at the National Institute of Standards and Technology
(NIST)  has developed guidance to help organizations protect their
information and information systems and to use security controls that
are selected through a risk-based process.

Development of NIST Special Publication (SP) 800-53, Recommended
Security Controls for Federal Information Systems

The basic questions that organizations should address when selecting
security controls are:  What controls are needed to protect systems,
while supporting their operations and safeguarding their assets?  Can
the selected controls be implemented?  And once implemented, are they
effective?  NIST SP 800-53, Recommended Security Controls for Federal
Information Systems, helps organizations to answer these questions and
to maintain effective information security programs. This ITL Bulletin
summarizes the special publication.

Written by Ron Ross, Stuart Katzke, Arnold Johnson, Marianne Swanson,
Gary Stoneburner, George Rogers, and Annabelle Lee, NIST SP 800-53 was
developed using input from a variety of sources including published
NIST standards and guidance, Department of Defense (DoD)  policies,
international standards, and other federal government directives and
policies. SP 800-53 provides guidance for federal agencies that
operate federal information systems other than those systems
designated as national security systems, as defined in 44 U.S.C.,
Section 3542. However, the security controls that are specified in
NIST SP 800-53 are complementary to similar guidance that has been
issued for national security systems.

NIST SP 800-53 was issued in final form in February 2005 after
extensive public input and review. The authors received many valuable
comments from government and private sectors that helped to shape the
final recommendations.  While primarily aimed toward helping federal
agencies achieve more secure information systems, other activities
including state, local and tribal governments, and private sector
organizations should find the guide useful in selecting and specifying
security controls for their information and information systems.

Understanding and Selecting Security Controls

Recommended Security Controls for Federal Information Systems provides
a foundation for understanding the fundamental concepts of security
controls. The introductory material presents the concept of security
controls and their use within a well-defined information security
program. Some of the issues discussed include the structural
components of controls, how the controls are organized into families,
and the use of controls to support information security programs. The
guide outlines the essential steps that should be followed to
determine needed controls, to assure the effectiveness of controls,
and to maintain the effectiveness of installed controls. A detailed
process for selecting and specifying appropriate security controls is

The publication's appendices provide additional resources including
general references, definitions, explanation of acronyms, a breakdown
of security controls for graduated levels of security requirements, a
catalog of security controls, and information relating security
controls to other standards and control sets. The controls in the
catalog are organized into classes of operational, management, and
technical controls, and then into families within each class. NIST
plans to review and to update the controls in the catalog as
technology changes and as new safeguards and new information security
countermeasures are identified.

NIST SP 800-53 is available in electronic format from the NIST
Computer Security Resource Center at

NIST SP 800-53 and FISMA Requirements

NIST SP 800-53 is one of the series of standards and guidelines that
NIST has developed to help federal agencies implement their
responsibilities under the Federal Information Security Management Act
(FISMA). FISMA requires that all federal agencies develop, document,
and implement agency-wide information security programs to protect the
information and information systems that support the operations and
assets of the agency, including those systems provided or managed by
another agency, contractor, or other source.

To support agencies in conducting their information security programs,
the FISMA directed NIST to develop:

* Standards for categorizing information and information systems
  collected or maintained by or on behalf of each federal agency based
  on the objectives of providing appropriate levels of information
  security according to a range of risk levels;

* Guidelines recommending the types of information and information
  systems to be included in each category; and

* Minimum information security requirements for information and
  information systems in each such category.

FIPS 199, Standards for Security Categorization of Federal Information
and Information Systems, issued in February 2004, addresses the first
task specified by FISMA. FIPS 199 requires that agencies categorize
their information systems as low-impact, moderate-impact, or
high-impact systems for the security objectives of confidentiality,
integrity, and availability. In a low-impact system, all security
objectives are low. If at least one of the security objectives is
moderate and no security objective is greater than moderate, the
system is moderate-impact. A high-impact system is one for which at
least one security objective is high. This categorization is the first
step in the agency’s risk management process, to be followed by the
selection of security controls that are appropriate for the impact
levels determined in the categorization procedure.

Draft FIPS 200, Minimum Security Requirements for Federal Information
and Information Systems, which is in the final stages of development,
will specify a risk-based approach for agencies to follow in
determining their minimum security requirements and for selecting
cost-effective security controls. NIST expects to announce FIPS 200
for public review and comment in the near future. In applying the
provisions of proposed FIPS 200, agencies will categorize their
systems as required by FIPS 199, and then select an appropriate set of
security controls from NIST SP 800-53.  These controls are the
foundation for the selection of adequate controls, but the final
determination of the appropriate set of controls depends upon the
organization’s assessment of risk.

Implementing an Effective Information Security Program

To maintain an effective information security program that protects
their information and information systems, organizations should follow
a systematic process to carry out these tasks:

* Periodically assess the risks that could result from the
  unauthorized access, use, disclosure, disruption, modification, or
  destruction of information and information systems that support the
  operations and assets of the organization;

* Adopt policies and procedures that are based on risk assessments,
  reduce risks cost-effectively to an acceptable level, and ensure 
  that information security is addressed throughout the life cycle of 
  the information system;

* Develop plans to provide information security for networks,
  facilities, information systems, or groups of information systems;

* Provide security awareness training to educate personnel about
  information security risks and responsibilities for following 
  policies and procedures that are designed to reduce risks;

* Periodically test and evaluate the effectiveness of information
  security policies, procedures, practices, and security controls;

* Use an organizational process to plan, implement, evaluate, and
  document remedial actions that address identified deficiencies;

* Adopt procedures that detect, report, and respond to security
  incidents; and

* Support plans and procedures to ensure continuity of 

A Risk-Based Approach to Selecting Controls

In adopting a risk-based approach to the selection of security
controls, organizations should consider the effectiveness and
efficiency needed in their systems, and the requirements that are
specified in applicable, laws, directives, executive orders, policies,
standards, and regulations. The following activities can be applied to
new and legacy information systems within the context of overall
life-cycle planning, including the planning guides in the System
Development Life Cycle and the Federal Enterprise Architecture:

* Categorize information systems and their information based on the
  procedures for categorizing systems that are detailed in FIPS 199.
  Based on the security categorization, select an initial set of
  security controls from the catalog of controls listed in Appendix D 
  of SP 800-53.

* Adjust the initial set of security controls based on an assessment
  of risk and local conditions including organization-specific 
  security requirements, specific threat information, cost-benefit 
  analyses, the availability of compensating controls, or special 

* Document the agreed-upon set of security controls taking into
  account any adjustments or refinements.

The Security Control Catalog

The security controls listed in the SP 800-53 catalog represent the
current state-of-the-practice safeguards and countermeasures for
information systems. These controls will be revised and extended as
experience is gained in using the controls, and as requirements and
technology change.

The security controls should be considered as the foundations or
starting points in the selection of controls for low-impact,
moderate-impact, and high-impact information systems, based on
categorizations done in accordance with FIPS 199. Since the
determination of adequate controls is based on the organization’s
determination of risk, additional controls may be needed to address
specific threats or particular organizational requirements.

The security controls cover the following seventeen areas:

* Risk assessment - including policies and procedures;  security
  categorization; and management of the risk assessment process.

* Certification, accreditation, and security assessments - including
  policies and procedures; control of system connections; management 
  of the accreditation process; and assessments and monitoring of 

* System services and acquisition - including policies and procedures;
  management of resource allocation, life cycle support, acquisitions,
  and system documentation; and control of software usage and of
  outsourced information services.

* Security planning - including policies and procedures;  development
  and implementation of plans; and management of staff behavior rules
  and privacy procedures.

* Configuration management - including policies and procedures;
  management of information system components;  and control and
  management of changes to information systems and to system settings.

* System and communications protection - including policies 
  and procedures; application partitioning; controls for 
  denial of service protection, resource use, boundary 
  protection, and telecommunications services; and management 
  of cryptography applications and public key infrastructure 

* Personnel security - including policies and procedures; 
  and management of staff positions, screening, terminations, 
  and transfers.

* Awareness and training - including policies and
  procedures; and management of the content of training and 
  of training records.

* Physical and environmental protection - including policies and
  procedures; management of access authorizations; controls for access
  to transmission facilities and display media; management of access
  logs and visitor controls; and management of power equipment, 
  cabling, lighting, fire protection, and alternate work sites.

* Media protection - including policies and procedures;  processes for
  media access, labeling, storage, transport, and sanitization; and
  destruction and disposal of media.

* Contingency planning - including policies and procedures;  
  contingency training; and development, maintenance, and testing of
  plans; management of alternate processing sites, telecommunications
  services, and information backup; and management of system recovery.

* Maintenance - including policies and procedures;  management of
  periodic maintenance; and control of maintenance tools and 
  maintenance personnel.

* System and information integrity - including policies and
  procedures; management of flaw protection, malicious code 
  protection, and intrusion detection; controls for security alerts, 
  and for software and information integrity; spam and spyware 
  protection; and error handling.

* Incident response - including policies and procedures;  incident
  training, testing, handling, monitoring, and reporting.

* Identification and authentication - including policies 
  and procedures; management of devices, identifiers, and 
  authenticators; and management of cryptographic processes.

* Access control - including policies and procedures;  access
  enforcement; information flow enforcement;  management of login
  attempts; system use notification;  remote access controls; and
  wireless access controls.

* Accountability and audit - including policies and procedures; audit
  processing; audit monitoring, analysis, and reporting; and audit
  report generation.

Using Security Controls to Improve Information System Security

NIST SP 800-53 provides detailed information about these seventeen
categories of broadly applicable security controls and helps
organizations select the controls that are appropriate for a wide
variety of security requirements. When correctly implemented and
periodically assessed for effectiveness, security controls can
contribute to organizational confidence that requirements for the
security of information systems are being met. The controls are a
starting point for risk assessments and play an important role in the
organization’s practices for comprehensive system security planning
and life cycle management.

The extensive reference list in SP 800-53 includes standards,
guidelines, and recommendations that organizations can use for their
comprehensive security planning and life cycle management processes.
These publications can be accessed from the NIST web pages at


Any mention of commercial products or reference to commercial
organizations is for information only; it does not imply
recommendation or endorsement by NIST nor does it imply that the
products mentioned are necessarily the best available for the purpose.

Elizabeth B. Lennon
Information Technology Laboratory
National Institute of Standards and Technology
100 Bureau Drive, Stop 8900
Gaithersburg, MD 20899-8900
Telephone (301) 975-2832
Fax (301) 840-1357

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