CMMC-CCP Cyber AB Exam Lab Questions

Understanding NIST SP 800-88 Rev. 1 and Media Sanitization

TheNIST Special Publication (SP) 800-88 Revision 1, Guidelines for Media Sanitization, provides guidance onsecure disposalof data from various types of storage media to prevent unauthorized access or recovery.

Three Categories of Data Disposal in NIST SP 800-88 Rev. 1

Clear

Useslogical techniquesto remove data from media, making it difficult to recover usingstandard system functions.

Example:Overwriting all datawith binary zeros or ones on a hard drive.

Applies to:Magnetic media, solid-state drives (SSD), and non-volatile memorywhen the media isreused within the same security environment.

Purge

Usesadvanced techniquesto make data recoveryinfeasible, even with forensic tools.

Example:Degaussinga magnetic hard drive orcryptographic erasure(deleting encryption keys).

Applies to:Media that is leaving organizational control or requires a higher level of assurance than " Clear " .

Destroy

Physicallydamages the mediaso that data recovery isimpossible.

Example:Shredding, incinerating, pulverizing, or disintegratingstorage devices.

Applies to:Highly sensitive data that must be permanently eliminated.

Why " A. Clear, Purge, Destroy " is Correct?

B. Clear, Redact, Destroy (Incorrect)– " Redact " is a term used for document sanitization,notdata disposal.

C. Clear, Overwrite, Purge (Incorrect)– " Overwrite " is a method within " Clear, " but it isnot a top-level categoryin NIST SP 800-88.

D. Clear, Overwrite, Destroy (Incorrect)– " Overwrite " is a sub-method of " Clear, " but " Purge " is missing, making this incorrect.

Conclusion

The correct answer isA. Clear, Purge, Destroy, as these are thethree official categoriesof data disposal inNIST SP 800-88 Revision 1.

Step 1: Understand the “CA” Domain – Security Assessment

TheCA (Security Assessment)domain includes practices related to:

Planning security assessments,

Performing periodic reviews,

Managing plans of action and milestones (POA & Ms).

These practices derive fromNIST SP 800-171, specifically:

CA.2.157– Develop, document, and periodically update security plans,

CA.2.158– Periodically assess security controls,

CA.2.159– Develop and implement POA & Ms.

✅Step 2: Review CMMC Levels

Level 1 (Foundational):

Implements only the17 practicesfromFAR 52.204-21

Doesnot include the CA domain

Level 2 (Advanced):

Implements110 practicesfromNIST SP 800-171, including CA.2.157–159

First levelwhereSecurity Assessment (CA)practices are required

Level 3:

Not yet finalized but intended to include selected controls fromNIST SP 800-172

❌Why the Other Options Are Incorrect

A. Level 1

✘No CA domain practices are present at Level 1.

C. Level 3 / D. Level 4

✘These levels build on CA practices but do not represent thestarting point.

TheSecurity Assessment (CA)domain practices begin atCMMC Level 2, as part of the implementation ofNIST SP 800-171.

Understanding Access Control in CMMC

Access control refers to the process ofgranting or denyingspecific requests to:

Obtain and use information

Access information processing services

Enter specific physical locations

TheAccess Control (AC) domain in CMMCis based onNIST SP 800-171 (3.1 Access Control family)and includes requirements to:

✅Implement policies for granting and revoking access.

✅Restrict access to authorized personnel only.

✅Protect physical and digital assets from unauthorized access.

Since the questionbroadly asks about the process of granting or denying access to information, services, and physical locations, the correct answer isA. Access Control.

Why the Other Answers Are Incorrect

B. Physical access control

❌Incorrect.Physical access controlis asubsetof access control that only applies tophysical locations(e.g., keycards, security guards, biometrics). The question includesinformation and services, makinggeneral access controlthe correct choice.

C. Mandatory access control (MAC)

❌Incorrect.MAC is a specific type of access controlwhere access is strictly enforced based onsecurity classifications(e.g., Top Secret, Secret, Confidential). The questiondoes not specify MAC, so this is incorrect.

D. Discretionary access control (DAC)

❌Incorrect.DAC is another specific type of access control, whereownersof data decide who can access it. The question asksgenerallyabout granting/denying access, makingaccess control (A)the best answer.

CMMC Official References

CMMC 2.0 Model - AC.L2-3.1.1 to AC.L2-3.1.22– Covers access control requirements, includingcontrolling access to information, services, and physical spaces.

NIST SP 800-171 (3.1 - Access Control Family)– Defines the general principles of access control.

Thus,option A (Access Control) is the correct answer, as it best aligns withCMMC access control requirements.

A Restricted Information System (IS) is defined as an asset that cannot meet modern security controls but is still needed for contract performance. These systems may be declared out of scope if they are properly isolated, mitigated, and documented. A legacy Windows 95 computer meets the definition of a restricted IS.

Supporting Extracts from Official Content:

CMMC Scoping Guide (Level 2): “Restricted IS assets are those that cannot reasonably apply security requirements due to legacy or operational constraints. They are not assessed but must be identified and protected by alternative methods.”

Why Option B is Correct:

The Windows 95 system is an example of a restricted IS, so it can be scoped out.

Option A is incorrect — the asset is not handling CUI in this case.

Option C is incorrect — government property designation does not define scope.

Option D is incorrect — while it is “legacy,” it is not classified as OT; the correct CMMC term is restricted IS.

References (Official CMMC v2.0 Content):

CMMC Scoping Guide, Level 1 and Level 2 – Restricted IS definition.

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