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Withdrawn on May 14, 2024. Superseded by SP 800-171 Rev. 3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
AC-3.1.1 Limit system access to authorized users, processes acting on behalf of authorized users, and devices (including other systems)
Control Family: Access Control
Control Type: Basic
SPRS Value: 5
CMMC Level(s):
AC.L1-b.1.i
AC.L2-3.1.1
Top Ten Failed Requirement:
No
Referenced in:
FAR Clause 52.204 b.1.i
DFARS 252.204-7012
Derived From: NIST SP 800-53r4
AC-2
AC-3
AC-17
Discussion:
Access control policies (e.g., identity- or role-based policies, control matrices, and cryptography) control access between active entities or subjects (i.e., users or processes acting on behalf of users) and passive entities or objects (e.g., devices, files, records, and domains) in systems. Access enforcement mechanisms can be employed at the application and service level to provide increased information security. Other systems include systems internal and external to the organization. This requirement focuses on account management for systems and applications. The definition of and enforcement of access authorizations, other than those determined by account type (e.g., privileged verses non-privileged) are addressed in requirement 3.1.2.
Determining Statements (NIST SP 800-171Ar2)
Upon assessment, assessors must determine if-
3.1.1[a] authorized users are identified.
3.1.1[b] processes acting on behalf of authorized users are identified.
3.1.1[c] devices (and other systems) authorized to connect to the system are identified.
3.1.1[d] system access is limited to authorized users.
3.1.1[e] system access is limited to processes acting on behalf of authorized users.
3.1.1[f] system access is limited to authorized devices (including other systems).
Assessors are instructed to-
Examine: [SELECT FROM: Access control policy; procedures addressing account management; system security plan; system design documentation; system configuration settings and associated documentation; list of active system accounts and the name of the individual associated with each account; notifications or records of recently transferred, separated, or terminated employees; list of conditions for group and role membership; list of recently disabled system accounts along with the name of the individual associated with each account; access authorization records; account management compliance reviews; system monitoring records; system audit logs and records; list of devices and systems authorized to connect to organizational systems; other relevant documents or records].
Interview: [SELECT FROM: Personnel with account management responsibilities; system or network administrators; personnel with information security responsibilities].
Test: [SELECT FROM: Organizational processes for managing system accounts; mechanisms for implementing account management].
Potential Solutions Based on Staffing
1-10 FTE |
10-49 FTE |
50-249 FTE |
250-999 FTE |
1000+ FTE |
|---|---|---|---|---|
| Microsoft AD | Microsoft AD | Microsoft AD | Microsoft AD | Microsoft AD |
| Azure AD SSO | Azure AD SSO | Azure AD SSO | Azure AD SSO | Azure AD SSO |
| Okta | Okta | Okta |