How to Scope CMMC Correctly: Avoid Audit Failures, Over-Scoping, and Cloud Risks

Is your CMMC scope setting you up for success—or failure?

In this episode of the CMMC Compliance Guide, Brooke and Stacey from Justice IT Consulting break down one of the most misunderstood (and expensive) parts of your compliance journey: scoping.

Learn how to define your CUI boundary the right way, avoid common over-scoping mistakes, and streamline your assessment with clear documentation strategies. Whether you're prepping for a formal CMMC assessment or self-assessing for NIST 800-171, this episode gives you real-world insights that can save you time, money, and frustration.

🔍 We cover:

• What really defines your CMMC scope (it's more than just your server)
• The hidden risks of over-scoping and cloud blind spots
• Third-party service provider mistakes that can blow your scope
• Must-have documentation: data flow diagrams, network diagrams, and asset inventories
• A practical checklist to get your scope right before the audit

🛠 Need a faster path to compliance without cutting corners? Visit www.CMMCComplianceGuide.com for free resources, expert help, or to book a discovery call.

Transcript

SPEAKER_01: 0:21

Hey there, welcome to the CMMC Compliance Guide Podcast. I'm Stacey.

SPEAKER_00: 0:25

And I'm Brooke.

SPEAKER_01: 0:26

From Justice IT Consulting, where we help businesses like yours navigate CMMC and NIST 800-171 compliance. We're hired guns getting companies fast-tracked to compliance, but today we're here to give you all the secrets for free, so if you want to tackle it yourself, you're equipped to do so. Let's dive into today's episode and keep your business on track. Today, we're zeroing in on CMMC scoping. And if you think it's just about checking a box on your SSP, think again. Scoping mistakes can tank your assessment, cost you tens of thousands in rework, or even disqualify you from contracts. Let's unpack how to define your boundary the right way. Brooke, why do so many contractors struggle with scoping? It seems like it should be pretty straightforward.

SPEAKER_00: 1:12

It does seem like it should be pretty straightforward. You know, you think, which of my systems should be in scope? And generally, if you don't think about it too much, you have a tendency to overscope and say, you know, everything. Especially if you're a small, medium-sized contractor, you know, you have a tendency to overscope a little bit. So it's common to overscope. That's just an easy thing to default to. So if you scope properly, and maybe your whole environment does have to be in scope, but you really have to really take everything into consideration and figure that out. Otherwise, it will lead to more cost, longer audits, all sorts of funds, and maybe unnecessarily higher cost or longer audits.

SPEAKER_01: 2:07

If we want to break this down simply, what are Really,

SPEAKER_00: 2:14

the things you need to take into account is it isn't just where your CUI, your digital CUI resides. You know, hey, it's my server. My server's, you know, in scope. It's going to be your data. It's going to be the people who... Who access that? It's going to be processes that touch that data. So those are going to be all the things that touch it. Whether you should create an enclave or not. So if you can create any kind of enclave where it makes your in-scope environment smaller, That's always the best approach. And then, of course, you always have to figure out which really kind of goes into processes, sort of. But you always have to figure in your third-party connections, your cloud vendors or any other partner companies that might have access to your data, any other MSPs who might have access to that data. Those third-party connections really matter.

SPEAKER_01: 3:17

Let's get into some common mistakes. What are some of the scenarios contractors need to watch out for?

SPEAKER_00: 3:24

Well, the first... The first mistake that you've got to watch out for, which is really common, and probably 99% of everybody did this early on, and it's overscoping, just as we talked about a minute ago. It's easy to say, well, I don't know exactly where I'm on my CUI is, and we'll just say everything's in scope. So overscoping is one of the common mistakes that people make. There's some cloud storage blind spots, I guess. So there's some cloud storage blind spots. Like you may forget that you upload or have something that uploads and keeps data in an Amazon browser. uh, Amazon, Amazon S3 bucket or anyway, something like that. Um, you may forget about something like that, but so you've got to really take a good data inventory and figure out where things are at. Uh, and then another one, uh, we kind of referenced a minute ago, uh, really, uh, mostly in relation to cloud providers or cloud services. Um, but as, uh, as a subcontractor or service provider oversight. So if there are any service providers that have access to your CUI, like backing it up, you know, something like that, then those people will come in scope as well.

SPEAKER_01: 4:51

When it comes to our favorite topic on the podcast, documentation, what do assessors expect to see done right?

SPEAKER_00: 4:59

So assessors are going to expect to see a network diagram done properly, right, and comprehensively. So most everybody's going to have a network diagram, but having a network diagram that actually encompasses everything that you have to keep in mind for CUI and for CMMC compliance. People don't normally have that, so you've really got to make sure that you have a very comprehensive network diagram in place. The other thing is asset inventories. This isn't just your computers that are on the network. That's what most people think of. It's easy to generate. You spit a list out of Active Directory or Azure Active Directory or your remote management monitoring solution, something like that. And people say, yep, here it is. Well, that's really not it. It's everything on that network that touches CUI that's in scope. or adjacent that you need to identify. And that's what an asset inventory is. The other thing is going to be, and really the first thing you should do, is a data flow diagram. You really need to have that data flow diagram to show where your data comes from, where it goes to, where it flows through your systems, and where it flows out of your systems. And that really is the very first thing you should do before you even attempt to Spell the word scope is do a data flow diagram because that helps you understand where everything's at. where it flows and everything so you know what's in scope or it also helps you realize that oh holy cow we probably need to narrow our scope a little bit and we need to take care of this data flow diagram and and um and bring less systems in into scope right uh so there's that data flow diagram is very very important for scoping it's all it'll also be very important the the assessors are going to want to see the data flow diagram

SPEAKER_01: 7:07

so brooke what's the broader business risk if contractors Don't scope correctly.

SPEAKER_00: 7:12

Well, so the broader risk is going to be that it could lead to– if you overscope, it could lead to something– it could lead to more– like we talked about a minute ago, it could lead to more time for the assessment, which means more dollars. Okay. If you don't scope properly and that's kind of figured out during the assessment, then magically things will be brought into scope that you didn't count on. And that could lead to either a more costly assessment or more likely a failed assessment. So really, if you scope properly... And you document everything, and you document, document, document. I should have worn my document, document, document T-shirt, so we gave some of those away at a recent conference, and they seem to be a hit. But if you document everything, you show where everything goes, you do your data flow diagram, you tell your story about your scope and why it's there, then not only will you have done a nice, thorough job of it, but you're going to be able to and be confident in the fact that you scope properly. But when the assessor reads that and sees your documentation, they'll feel very confident too. Because I can tell you, if the assessor doesn't feel confident in anything, the scoping or data flow diagram, whatever it may be, but if they don't feel confident in the scoping, they're going to delve a little deeper.

SPEAKER_01: 8:51

So to give our listeners a little bit of some actionable takeaways, what is a good checklist that our listeners could follow to avoid these common pitfalls

SPEAKER_00: 9:00

with scoping? So as far as the checklist goes, that you can kind of follow, you start with your contract, right? And any documents that you get that may be labeled CUI, but you need to figure out what kind of CUI you have, what contracts they're part of, right? And so you can identify that type of CUI and hopefully the... data flow diagram where it goes. You can walk your physical spaces and tag your systems visually so you can see what handles CUI, and it's easy to see. Interview your teams, and this way you can spot shadow IT, of course. But you also may realize that the way you imagine that they are doing things they may not actually be doing them that way and they may inform you that they do it a little bit different and it either leave something out of scope that you included and shouldn't have, or it may be that you have to include something else in the scope, for instance. So it's good to talk to your team members and make sure that you really do understand how things are being done. So you could review, for instance, you could probably review your bills for cloud services and then some of the logs to identify where there may be some CUI issues going, or if it's something that you haven't, you know, if you identify, say, hey, what's this Amazon bill for? Or, well, I guess it could be all over the place, but, you know, Amazon cloud services bill, what is this for? I didn't think we did anything. So review your bills, make sure you know what you're paying for, and then see if you've left anything out of scope. That's always a good thing to make sure of. And the last thing is document everything. Again, documentation, documentation, documentation. You've got to document everything, just a ton of documentation. Make sure it's comprehensive but concise, I would say. I know that can be at odds, but really it needs to be nice and comprehensive but not complex. too lengthy, you need to keep it as concise as possible for your own sake and for the assessor's sake. Because, you know, do you really want them to read through a SSP that's, you know, 350 pages long, you know? And it may be so if you don't have any policies, and that's where all your policies are. But generally, you should try to be comprehensive, but make sure everything is nice and concise.

SPEAKER_01: 11:50

Looks like that wraps up today's episode. If you have any questions about what we covered, please reach out to us. We're here to help fast track your compliance journey. Text, email, or call in your questions and we'll answer them for free here on the podcast. You can find our contact information at cmmccomplianceguide.com. Stay tuned for our next episode. Until then, stay compliant and stay secure. Like, subscribe, and share.