NIST Special Publication 800-171 Revision 2

Date Published: January 28th, 2021

Withdrawn on May 14, 2024. Superseded by SP 800-171 Rev. 3

Author(s): Ron Ross (NIST), Victoria Pillitteri (NIST), Kelley Dempsey (NIST), Mark Riddle (NARA), Gary Guissanie (IDA)

Note: A Class Deviation is in effect as of May 2, 2024 (DEVIATION 2024O0013). The deviation clause requires contractors, who are subject to 252.204-7012, to comply with National Institute of Standards and Technology (NIST) Special Publication (SP) 800-171 Revision 2, instead of the version of NIST SP 800-171 in effect at the time the solicitation is issued or as authorized by the contracting officer. Click Here

3.13.11: Employ FIPS-validated cryptography when used to protect the confidentiality of CUI.

Control Family: System and Communications Protection

Control Type: Derived

SPRS Value: 3/5

SPRS Supplemental Guidance: N/A

CMMC Level(s):

  • SC.L2-3.13.11

Top Ten Failed Requirement:

No

Referenced in:

DFARS 252.204-7012

Derived From: NIST SP 800-53r4

  • SC-13

NIST Supplemental Guidance:

  • [NIST CRYPTO]

  • [NIST CAVP]

  • [NIST CMVP]

Discussion:

Cryptography can be employed to support many security solutions including the protection of controlled unclassified information, the provision of digital signatures, and the enforcement of information separation when authorized individuals have the necessary clearances for such information but lack the necessary formal access approvals. Cryptography can also be used to support random number generation and hash generation. Cryptographic standards include FIPSvalidated cryptography and/or NSA-approved cryptography. See [NIST CRYPTO]; [NIST CAVP]; and [NIST CMVP].

Upon assessment, assessors must determine if-

3.13.10[a] cryptographic keys are established whenever cryptography is employed.
3.13.10[b] cryptographic keys are managed whenever cryptography is employed.

Assessors are instructed to-

Examine: [SELECT FROM: System and communications protection policy; procedures addressing cryptographic protection; system security plan; system design documentation; system configuration settings and associated documentation; cryptographic module validation certificates; list of FIPS-validated cryptographic modules; system audit logs and records; other relevant documents or records].

Interview: [SELECT FROM: System or network administrators; personnel with information security responsibilities; system developer; personnel with responsibilities for cryptographic protection].

Test: [SELECT FROM: Mechanisms supporting or implementing cryptographic protection].

FURTHER DISCUSSION

FIPS-validated cryptography means the cryptographic module has to have been tested and validated to meet FIPS 140-2 requirements. Simply using an approved algorithm is not sufficient – the module (software and/or hardware) used to implement the algorithm must be separately validated under FIPS 140. Accordingly, FIPS-validated cryptography is required to protect CUI when transmitted or stored outside the protected environment of the covered OSA information system (including wireless/remote access). Encryption used for other purposes, such as within applications or devices within the protected environment of the covered OSA information system, would not need to use FIPS-validated cryptography. This requirement, SC.L2-3.13.11, complements AC.L2-3.1.19, MP.L2-3.8.6, SC.L2-3.13.8, and SC.L2-3.13.16 by specifying that FIPS-validated cryptography must be used. While FIPSvalidated modules and algorithms are critical for protecting CUI, in limited cases Enduring Exceptions and temporary deficiencies may apply when implementing such cryptographic mechanisms.

Example

You are a system administrator responsible for deploying encryption on all devices that contain CUI. You must ensure that the encryption you use on the devices is FIPS-validated cryptography [a]. An employee informs you of a need to carry a large volume of CUI offsite and asks for guidance on how to do so. You provide the user with disk encryption software that you have verified via the NIST website that uses a CMVP-validated encryption module [a]. Once the encryption software is active, the user copies the CUI data onto the drive for transport.

Potential Assessment Considerations

  • Is cryptography implemented to protect the confidentiality of CUI at rest and in transit, through the configuration of systems and applications or through the use of encryption tools [a]?

Frameworks & Controls