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Withdrawn on May 14, 2024. Superseded by SP 800-171 Rev. 3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-3.1.5 Employ the principle of least privilege, including for
specific security functions and privileged accounts.
Control Family: Access Control
Control Type: Derived
SPRS Value: 1
CMMC Level(s):
AC.L2-3.1.5
Top Ten Failed Requirement:
No
Referenced in:
DFARS 252.204-7012
Derived From: NIST SP 800-53r4
AC-6
AC-6(1)
AC-6(5)
Discussion:
Organizations employ the principle of least privilege for specific duties and authorized accesses for users and processes. The principle of least privilege is applied with the goal of authorized privileges no higher than necessary to accomplish required organizational missions or business functions. Organizations consider the creation of additional processes, roles, and system accounts as necessary, to achieve least privilege. Organizations also apply least privilege to the development, implementation, and operation of organizational systems. Security functions include establishing system accounts, setting events to be logged, setting intrusion detection parameters, and configuring access authorizations (i.e., permissions, privileges). Privileged accounts, including super user accounts, are typically described as system administrator for various types of commercial off-the-shelf operating systems. Restricting privileged accounts to specific personnel or roles prevents day-to-day users from having access to privileged information or functions. Organizations may differentiate in the application of this requirement between allowed privileges for local accounts and for domain accounts provided organizations retain the ability to control system configurations for key security parameters and as otherwise necessary to sufficiently mitigate risk.
Determining Statements (NIST SP 800-171Ar2)
Upon assessment, assessors must determine if-
3.1.5[a] privileged accounts are identified.
3.1.5[b] access to privileged accounts is authorized in accordance with the principle of
least privilege.
3.1.5[c] security functions are identified.
3.1.5[d] access to security functions is authorized in accordance with the principle of
least privilege.
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; list of conditions for group and role membership; notifications or records of recently transferred, separated, or terminated employees; 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/audit records; procedures addressing least privilege; list of security functions (deployed in hardware, software, and firmware) and security-relevant information for which access is to be explicitly authorized; list of system-generated privileged accounts; list of system administration personnel; other relevant documents or records].
Interview: [SELECT FROM: Personnel with account management responsibilities; system or network administrators; personnel with information security responsibilities; personnel with responsibilities for defining least privileges necessary to accomplish specified tasks].
Test: [SELECT FROM: Organizational processes for managing system accounts; mechanisms for implementing account management; mechanisms implementing least privilege functions; mechanisms prohibiting privileged access to the system].
Potential Solutions Based on Staffing
1-10 FTE |
10-49 FTE |
50-249 FTE |
250-999 FTE |
1000+ FTE |
---|---|---|---|---|
Microsoft AD | Microsoft AD | CyberArk | CyberArk | CyberArk |
Azure AD SSO | Azure AD SSO | Centrify | Centrify | Centrify |
Cimcor CimTrack | Cimcor CimTrack | Microsoft AD | Microsoft AD | Microsoft AD |
Netwrix Auditor | Netwrix Auditor | Azure AD SSO | Azure AD SSO | Azure AD SSO |
Microsoft Intune | Microsoft Intune | Okta | Okta | Okta |
DISA STIGs | DISA STIGs | Cimcor CimTrack | Cimcor CimTrack | Cimcor CimTrak |
CIS Benchmarks | CIS Benchmarks | Netwrix Auditor | Netwirx Auditor | Netwirx Auditor |
CIS SecureSuite | CIS SecureSuite | Microsoft Intune | Microsoft Intune | Microsoft Intune |
Tripwire Enterprise | Tripwire Enterprise | Tripwire Enterprise | ||
DISA STIGs | DISA STIGs | DISA STIGs | ||
CIS Benchmarks | CIS Benchmarks | CIS Benchmarks | ||
CIS SecureSuite | CIS SecureSuite | CIS SecureSuite |