Understanding Multi-Function Device (MFD) Security in CMMC
Multi-function devices (MFDs), such asscanners, printers, and copiers,process, store, and transmit FCI, making them apotential attack surfacefor unauthorized access.
Thebest technical controlto limit MFD access to only authorized systems isVirtual LAN (VLAN) restrictions, whichsegment and isolate network traffic.
Why the Correct Answer is "A. Virtual LAN (VLAN) Restrictions"?
VLAN Restrictions Provide Network Segmentation
VLANsisolate the MFDfrom unauthorized systems, ensuringonly approved devicescan communicate with it.
Prevents unauthorized network access bylimiting connectionsto specific IPs or subnets.
Meets CMMC 2.0 Network Security Controls
Aligns withCMMC System and Communications Protection (SC) Practicesfor network segmentation and access control.
Reducesthe risk of unauthorized access to scanned and printed FCI.
Why Not the Other Options?
B. Single administrative account→Incorrect
Asingle admin accountdoes not restrict accessbetween devices, only controlswho can configurethe MFD.
C. Documentation showing MFD configuration→Incorrect
Documentation helps with compliance butdoes not actively restrict access.
D. Access lists only known to the IT administrator→Incorrect
Access lists should besystem-enforced, not just "known" to the administrator.
Relevant CMMC 2.0 References:
CMMC Practice SC.3.192 (Network Segmentation)– Requires restricting access usingnetwork segmentation techniques such as VLANs.
NIST SP 800-171 (SC Family)– Supportsisolation of sensitive devicesusing VLANs and other segmentation controls.
Final Justification:
SinceVirtual LAN (VLAN) restrictions enforce access control at the network level, the correct answer isA. Virtual LAN (VLAN) restrictions.
