NIST 800-53 REV 5 • ACCESS CONTROL

AC-20(3)Non-organizationally Owned Systems — Restricted Use

Restrict the use of non-organizationally owned systems or system components to process, store, or transmit organizational information using {{ insert: param, ac-20.03_odp }}.

CMMC Practice Mapping

No direct CMMC mapping

NIST 800-171 Mapping

No direct NIST 800-171 mapping

Related Controls

No related controls listed

Supplemental Guidance

Non-organizationally owned systems or system components include systems or system components owned by other organizations as well as personally owned devices. There are potential risks to using non-organizationally owned systems or components. In some cases, the risk is sufficiently high as to prohibit such use (see [AC-20 b.](#ac-20_smt.b) ). In other cases, the use of such systems or system components may be allowed but restricted in some way. Restrictions include requiring the implementation of approved controls prior to authorizing the connection of non-organizationally owned systems and components; limiting access to types of information, services, or applications; using virtualization techniques to limit processing and storage activities to servers or system components provisioned by the organization; and agreeing to the terms and conditions for usage. Organizations consult with the Office of the General Counsel regarding legal issues associated with using personally owned devices, including requirements for conducting forensic analyses during investigations after an incident.

Practitioner Notes

Restrict the use of non-organizationally owned systems. If the device is not yours, you cannot guarantee its security posture.

Example 1: Create a Conditional Access policy in Azure AD that allows access only from devices that are Intune-enrolled and compliant. Any device not managed by your organization is blocked. This effectively prevents access from personal devices, public computers, and partner systems.

Example 2: If you must allow BYOD access, restrict it to a virtual desktop (Azure Virtual Desktop, Citrix) that runs in your environment. The personal device is just a display — no data is stored on it, and all processing happens in your controlled environment.