Knowledge is Power

Sitewide Search

Search Bare Metal Cyber

Search courses, individual lessons, wiki entries, books, podcasts, magazine articles, Daily Cyber News, and Darwin.

NIST SP 800-172 Enhanced CUI Protection Center

03.13.13E — Port and Input/Output Device Access

Read the official CUI requirement and assessment content, then use the separately labeled Bare Metal Cyber perspective to connect it to implementation, evidence, and sustained operation.

3Parameters
1Source controls
1Assessment objectives
3Assessment methods

03.13 — System and Communications Protection · NIST SP 800-172 Revision 3

Active
Official NIST requirement content

Security requirement

[Organization-defined: connection ports or input/output devices] disable or remove [Organization-defined: SELECTED PARAMETER VALUE] on the following systems or system components: [Organization-defined: systems or system components].

Official NIST discussion

Discussion

Connection ports include Universal Serial Bus (USB), Thunderbolt, and Firewire (IEEE 1394). Input/output (I/O) devices include optical drives (e.g., compact disc and digital versatile disc drives), printers, and network attached storage devices. Disabling or removing such connection ports and I/O devices helps prevent the exfiltration of information from systems and the introduction of malicious code from those ports or devices. Physically disabling or removing ports and/or devices is the stronger action. This requirement does not enhance a specific requirement in SP 800-171 but can be used to strengthen the protection of CUI associated with critical programs or high value assets.

Official organization-defined parameters

Tailoring decisions required

Resolve these values through the governing organization’s approved tailoring and risk-management process before declaring the requirement implemented.

connection ports or input/output devicesorganization-defined connection ports or input/output devicesconnection ports or input/output devices to be disabled or removed are defined.
SELECTED PARAMETER VALUE
systems or system componentsorganization-defined systems or system componentssystems or system components with connection ports or input/output devices to be disabled or removed are defined.
Official protection strategy classifications

Protection strategies supported

These classifications are carried from the official SP 800-172 OSCAL record and help explain the enhanced requirement’s defensive purpose.

PS-PRAPenetration-Resistant Architecture
Bare Metal Cyber interpretation

Implementation perspective

Treat Port and Input/Output Device Access as an enhanced CUI protection outcome for elevated threat conditions that must be reflected in the system boundary, documented implementation, operational behavior, and assessment evidence. Pay particular attention to secure architecture, boundary protection, communications security, cryptography, and isolation of CUI processing.

  1. Confirm the federal agency selected this enhanced requirement for the critical program or high-value asset and identify the CUI system components, services, users, and external connections in scope.
  2. Resolve every organization-defined parameter through an approved governance and tailoring process.
  3. Map each clause of the requirement to an accountable owner, implementation mechanism, and evidence source.
  4. Verify that inherited and shared implementations are supported by current provider evidence and responsibility boundaries.
  5. Collect evidence during normal operation and review changes, exceptions, and deficiencies on a risk-based cadence.

Questions to ask

  • Which critical-program or high-value-asset CUI, data flows, users, and services are protected by this enhanced requirement?
  • Which portions are implemented locally, inherited, shared, or not applicable, and what evidence supports that determination?
  • Do the system security plan, deployed configuration, operating process, and assessment evidence tell the same story?
  • What change, incident, or threshold should trigger reassessment?

Evidence and validation

  • network and trust-boundary diagrams
  • firewall and gateway configurations
  • cryptographic configuration and key records
  • segmentation and isolation test results

Common failure patterns

  • diagrams omitting cloud and third-party paths
  • encryption enabled without key governance
  • flat trust zones permitting unnecessary lateral movement
  • boundary rules accumulating without owner review
Official NIST SP 800-172A content

Assessment objectives and methods

Assessment objectives (1)
  1. [Organization-defined: connection ports or input/output devices] are [Organization-defined: SELECTED PARAMETER VALUE] disabled or removed on [Organization-defined: systems or system components].

Examine

  • System and communications protection policy
  • access control policy and procedures
  • procedures addressing port and input/output device access
  • system design documentation
  • system architecture
  • system configuration settings and associated documentation
  • systems or system components
  • list of connection ports or input/output devices to be physically disabled or removed on systems or system components
  • system security plan
  • other relevant documents or records

Interview

  • System/network administrators
  • personnel with information security responsibilities
  • personnel installing, configuring, and/or maintaining the system

Test

  • Mechanisms supporting and/or implementing the disabling of connection ports or input/output devices
Official source-control relationships

Source NIST SP 800-53 controls

These controls are referenced by the official SP 800-172 Rev. 3 OSCAL record. Open the corresponding control pages for complete control text, enhancements, D3FEND mappings, and related learning.

Source record

Authoritative sources