03.08.08: Shared Media

Beyond CMMC Level 1

The free web app covers the 17 CMMC Level 1 practices. This requirement is part of the full NIST 800-171 set — get the desktop app to work on all 110 requirements with SPRS scoring. Previously saved data is shown read-only below, and your data always remains exportable in full.

Get the desktop app

Security Requirements for 03.08.08 Shared Media

Requiring identifiable owners (e.g., individuals, organizations, or projects) for portable storage devices reduces the overall risk of using such technologies by allowing organizations to assign responsibility and accountability for addressing known vulnerabilities in the devices (e.g., insertion of malicious code).

Assessment GuidanceExamine 0/9

How an assessor determines this requirement is met. Source: CMMC Assessment Guide – Level 2, Version 2.13 (NIST SP 800-171 Rev. 2).

Discussion

A portable storage device is a system component that can be inserted into and removed from a system and is used to store data or information. It typically plugs into a laptop or desktop port (e.g., USB port). These devices can contain malicious files that can lead to a compromise of a connected system. Therefore, use should be prohibited if the device cannot be traced to an owner who is responsible and accountable for its security.

This requirement, MP.L2-3.8.8, furthers the protections provided by MP.L2-3.8.7 by prohibiting unidentified media use even if that media type is allowable.

Examples

Example 1
You are the IT manager. One day, a staff member reports finding a USB drive in the parking lot. You investigate and learn that there are no labels on the outside of the drive to indicate who might be responsible for it. You send an email to all employees to remind them that IT policies expressly prohibit plugging unknown devices into company computers. You also direct staff members to turn in to the IT help desk any devices that have no identifiable owner [a].

Assessment Methods

Examine

The process of reviewing, inspecting, observing, studying, or analyzing assessment objects (e.g., policies, procedures, plans, system designs, mechanisms) to facilitate understanding, achieve clarification, or obtain evidence.Example: An assessor reads the access control policy and inspects system configuration settings to confirm they match.

Not all of the evidence listed is required to meet this requirement — check the items your organization has collected.

System media protection policy
System use policy
Procedures addressing media usage restrictions
System security plan
Rules of behavior
System configuration settings and associated documentation
System design documentation
System audit logs and records
Other relevant documents or records

Interview

The process of holding discussions with individuals or groups within an organization to facilitate understanding, achieve clarification, or identify the location of evidence.Example: An assessor asks a system administrator to describe how user accounts are approved, reviewed, and disabled.

Personnel with system media use responsibilities
Personnel with information security responsibilities
System or network administrators

Test

The process of exercising assessment objects (e.g., activities, mechanisms) under specified conditions to compare actual behavior with expected behavior.Example: An assessor attempts to sign in with a disabled account to confirm that access is denied.

Organizational processes for media use
Mechanisms prohibiting use of media on systems or system components

Potential Assessment Considerations

Do portable storage devices used have identifiable owners [a]?

Key References

NIST SP 800-171 Rev. 2 3.8.8

Overview