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Withdrawn on May 14, 2024. Superseded by SP 800-171 Rev. 3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

3.5.2 Authenticate (or verify) the identities of users, processes, or devices, as a prerequisite to allowing access to organizational systems.

Control Family: Identification and Authentication

Control Type: Basic

SPRS Value: 5

SPRS Supplemental Guidance: N/A

CMMC Level(s):

IA.L1-b.1.vi
IA.L2-3.5.2

Top Ten Failed Requirement: No

Referenced in:

DFARS 252.204-7012

Derived From: NIST SP 800-53r4

  • IA-2

  • IA-3

  • IA-5

NIST Supplemental Guidance:

N/A

Discussion:

Individual authenticators include the following: passwords, key cards, cryptographic devices, and one-time password devices. Initial authenticator content is the actual content of the authenticator, for example, the initial password. In contrast, the requirements about authenticator content include the minimum password length. Developers ship system components with factory default authentication credentials to allow for initial installation and configuration. Default authentication credentials are often well known, easily discoverable, and present a significant security risk.

Systems support authenticator management by organization-defined settings and restrictions for various authenticator characteristics including minimum password length, validation time window for time synchronous one-time tokens, and number of allowed rejections during the verification stage of biometric authentication. Authenticator management includes issuing and revoking, when no longer needed, authenticators for temporary access such as that required for remote maintenance. Device authenticators include certificates and passwords.

[SP 800-63-3] provides guidance on digital identities.

Upon assessment, assessors must determine if-

3.5.2[a] the identity of each user is authenticated or verified as a prerequisite to system
access.
3.5.2[b] the identity of each process acting on behalf of a user is authenticated or
verified as a prerequisite to system access.
3.5.2[c] the identity of each device accessing or connecting to the system is
authenticated or verified as a prerequisite to system access.

Assessors are instructed to-

Examine: [SELECT FROM: Identification and authentication policy; system security plan; procedures addressing authenticator management; procedures addressing user identification and authentication; system design documentation; list of system authenticator types; system configuration settings and associated documentation; change control records associated with managing system authenticators; system audit logs and records; other relevant documents or records].

Interview: [SELECT FROM: Personnel with authenticator management responsibilities; personnel with information security responsibilities; system or network administrators].

Test: [SELECT FROM: Mechanisms supporting or implementing authenticator management capability].

FURTHER DISCUSSION

Before a person or device is given system access, verify that the user or device is who or what it claims to be. This verification is called authentication. The most common way to verify identity is using a username and a hard-to-guess password. Some devices ship with default usernames and passwords. Some devices ship with a default username (e.g., admin) and password. A default username and password must be immediately changed to something unique. Default passwords may be well known to the public, easily found in a search, or easy to guess, allowing an unauthorized person to access the system.

Example 1

You are in charge of purchasing. You know that some laptops come with a default username and password. You notify IT that all default passwords should be reset prior to laptop use [a]. You ask IT to explain the importance of resetting default passwords and convey how easily they are discovered using internet searches during next week’s cybersecurity awareness training.

Example 2

Your company decides to use cloud services for email and other capabilities. Upon reviewing this requirement, you realize every user or device that connects to the cloud service must be authenticated. As a result, you work with your cloud service provider to ensure that only properly authenticated users and devices are allowed to connect to the system [a,c].

Potential Assessment Considerations

  • Are unique authenticators used to verify user identities (e.g., passwords) [a]?

  • An example of a process acting on behalf of users could be a script that logs in as a person or service account [b]. Can the OSA show that it maintains a record of all of those service accounts for use when reviewing log data or responding to an incident?

  • Are user credentials authenticated in system processes (e.g., credentials binding, certificates, tokens) [b]?

  • Are device identifiers used in authentication processes (e.g., MAC address, nonanonymous computer name, certificates) [c]?