LLMPrompt AC.L2-3.1.1

I am a cybersecurity manager working for an organization that is a DoD contractor. I need to implement various security practices that conform to DoD's CMMC program at level 2. The CMMC program stipulates security practices that are based on NIST Special Publication 800-171 R2. For each security practice of CMMC Level 2, I need to show evidence that my organization is in compliance with CMMC. Each security practice has a security requirement and several assessment objectives that support that high-level security requirement.

I am assessing one of the assessment objectives within the practice AC.L2-3.1.1 – AUTHORIZED ACCESS CONTROL. The CMMC program has published the following assessment guidance, so take them into account as you formulate your response. Also refer to the attached CMMC Level 2 Assessment Guide, AssessmentGuideL2v2.pdf, for more context and information about the practice.

A. SECURITY REQUIREMENT: Limit information system access to authorized users, processes acting on behalf of authorized users, or devices (including other information systems).

B. ASSESSMENT OBJECTIVES [NIST SP 800-171A]: Determine if: [a] authorized users are identified; [b] processes acting on behalf of authorized users are identified; [c] devices (and other systems) authorized to connect to the system are identified; [d] system access is limited to authorized users; [e] system access is limited to processes acting on behalf of authorized users; and [f] system access is limited to authorized devices (including other systems).

C. ASSESSMENT APPROACH AND OBJECTS: I have three assessment approaches for assessing any security practice. They are listed as follows:

C1. Examine: The process of checking, inspecting, reviewing, observing, studying, or analyzing one or more assessment objectives to facilitate understanding, achieve clarification, or obtain evidence. The results are used to support the determination of security safeguard existence, functionality, correctness, completeness, and potential for improvement over time.

C2. Interview: The process of conducting discussion with individuals or groups of individuals in an organization to facilitate understanding, achieve clarification, or lead to the location of evidence. The results are used to support the determination of security safeguard existence, functionality, correctness, completeness, and potential for improvement over time.

C3. Test: The process of exercising one or more assessment objects under specified conditions to compare actual with expected behavior. The results are used to support the determination of security safeguard existence, functionality, correctness, completeness, and potential for improvement over time.

D. ASSESSMENT OBJECTS: Each assessment approach can yield potential assessment objects:

D1. Examine: SELECT FROM: Access control policy; procedures addressing account management; system security plan; system design documentation; system configuration settings and associated documentation; list of active system accounts and the name of the individual associated with each account; notifications or records of recently transferred, separated, or terminated employees; list of conditions for group and role membership; list of recently disabled system accounts along with the name of the individual associated with each account; access authorization records; account management compliance reviews; system monitoring records; system audit logs and records; list of devices and systems authorized to connect to organizational systems; other relevant documents or records.

D2. Interview: SELECT FROM: Personnel with account management responsibilities; system or network administrators; personnel with information security responsibilities.

D3: Test: SELECT FROM: Organizational processes for managing system accounts; mechanisms for implementing account management.

The previously mentioned assessment objects should help to support the recommended evidence.

E. DISCUSSION: Access control policies (e.g., identity- or role-based policies, control matrices, and cryptography) control access between active entities or subjects (i.e., users or processes acting on behalf of users) and passive entities or objects (e.g., devices, files, records, and domains) in systems. Access enforcement mechanisms can be employed at the application and service level to provide increased information security. Other systems include systems internal and external to the organization. This requirement focuses on account management for systems and applications. The definition of and enforcement of access authorizations, other than those determined by account type (e.g., privileged verses [sic] non-privileged) are addressed in requirement 3.1.2 (AC.L1-3.1.2).

F. FURTHER DISCUSSION: Identify users, processes, and devices that are allowed to use company computers and can log on to the company network. Automated updates and other automatic processes should be associated with the user who initiated (authorized) the process. Limit the devices (e.g., printers) that can be accessed by company computers. Set up your system so that only authorized users, processes, and devices can access the company network. This practice, AC.L1-3.1.1, controls system access based on user, process, or device identity. AC.L1-3.1.1 leverages IA.L1-3.5.1 which provides a vetted and trusted identity for access control.

G. EXAMPLES:

G1. Example 1: Your company maintains a list of all personnel authorized to use company information systems [a]. This list is used to support identification and authentication activities conducted by IT when authorizing access to systems [a,d].

G2. Example 2: A coworker wants to buy a new multi-function printer/scanner/fax device and make it available on the company network. You explain that the company controls system and device access to the network and will prevent network access by unauthorized systems and devices [c]. You help the coworker submit a ticket that asks for the printer to be granted access to the network, and appropriate leadership approves the device [f].

H. Potential Assessment Considerations: Is a list of authorized users maintained that defines their identities and roles [a]? Are account requests authorized before system access is granted [d,e,f]?

I. EVIDENCE TYPES: Finally, I have four evidence types that I can collect. The definitions of the evidence types are as follows:

I1. Artifacts: Tangible and reviewable records that are the direct outcome of a practice or process being performed by a system, person, or persons performing a role in that practice, control, or process. (See CAP Glossary for additional details.)

I2. Document: Any tangible thing which constitutes or contains information and means the original and any copies (whether different from the originals because of notes made on such copies or otherwise) of all writing of every kind and description over which an agency has authority. (See CAP Glossary for additional details.)

I3. Physical Review: An on-premise observation of Evidence.

I4. Screen Share: Live observation ""over the shoulder"" of a user as they share their computer screen while performing a task.

J. KEY REFERENCES: NIST SP 800-171 Rev 2 3.1.1