DISCUSSION [NIST SP 800-171 R2]

Cryptographic key management and establishment can be performed using manual procedures or mechanisms supported by manual procedures. Organizations define key management requirements in accordance with applicable federal laws, Executive Orders, policies, directives, regulations, and standards specifying appropriate options, levels, and parameters.

NIST SP 800-56A and NIST SP 800-57-1 provide guidance on cryptographic key management and key establishment.

FURTHER DISCUSSION

Develop processes and technical mechanisms to protect the cryptographic keys’ confidentiality, authenticity, and authorized use in accordance with industry standards and regulations. Key management systems provide oversight, assurance, and the capability to demonstrate the cryptographic keys are created in a secure manner and protected from loss or misuse throughout their lifecycle (e.g., active, expired, revoked). For a small number of keys, this can be accomplished with manual procedures and mechanisms. As the number of keys and cryptographic units increase, automation and tool support will be required.

The first intent of this practice is to ensure cryptographic keys are properly created in a secure manner that prevents them from being reproduced by an adversary. The second intent of this practice is to ensure cryptographic keys are managed in a secure manner that prevents them from being stolen by an adversary.

Key establishment involves the creation of keys and coordination among parties that will use the keys of the methodology for generating the final keying material. This is discussed in detail in SP 800-56A, B, and C.

Key management involves protecting keys when they are distributed, when they are stored, when they are being used, and when they are being recovered.

Key establishment best practices are identified in NIST SP 800-56A, B, and C. Key management best practices are identified in NIST SP 800-57 Parts 1, 2, and 3.

This practice, SC.L2-3.13.10, complements AC.L2-3.1.19 by specifying that any cryptographic keys in use must be protected.

Example 1

You are a system administrator responsible for providing key management. You have generated a public-private key pair to exchange CUI [a]. You require all system administrators to read the key management policy before you allow them to install the private key on their machines [b]. No one else is allowed to know or have a copy of the private key per the policy. You provide the public key to the other parties who will be sending you
CUI and test the Public Key Infrastructure (PKI) to ensure the encryption is working [a]. You set a revocation period of one year on all your certificates per organizational policy [b].

Example 2

You encrypt all of your company’s computers using the disk encryption utility built into the operating system. As you configure encryption on each device, it generates a cryptographic key. You associate each key with the correct computer in your inventory spreadsheet and restrict access to the spreadsheet to the system administrators whose work role requires them to manage the computers [b].

Potential Considerations

Are cryptographic keys established whenever cryptography is employed (e.g., digital signatures, authentication, authorization, transport, or other cryptographic mechanisms) [a]?

Are cryptographic keys maintained whenever cryptography is employed (e.g., key storage, backup, recovery, revocation, destruction, etc.) [b]?

Copyright

Copyright 2020, 2021 Carnegie Mellon University and The Johns Hopkins University Applied Physics Laboratory LLC.

Copyright 2021 Futures, Inc.

This material is based upon work funded and supported by the Department of Defense under Contract No. FA8702-15-D-0002 with Carnegie Mellon University for the operation of the Software Engineering Institute, a federally funded research and development center, and under Contract No. HQ0034-13-D-0003 and Contract No. N00024-13-D-6400 with the Johns Hopkins University Applied Physics Laboratory LLC, a University Affiliated Research Center.

The view, opinions, and/or findings contained in this material are those of the author(s) and should not be construed as an official Government position, policy, or decision, unless designated by other documentation.

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