NIST SP 800-53 Rev. 5 AC-2 — Account Management : iCompaas Support

NIST SP 800-53 Rev. 5·Control AC-2·high·Component: Access Control

What this control requires

Define and document allowed and prohibited system account types. Assign account managers, set criteria for group/role membership, and specify authorized users, access privileges, and attributes. Require approvals for account creation, manage accounts per policy, monitor usage, and notify managers of changes. Authorize access based on valid authorization and usage. Review accounts regularly, manage shared account authenticators, and align with personnel processes. This control supports the Governance capability within the Access Control family.
— NIST SP 800-53 Rev. 5, Control AC-2

In plain English

Define and document allowed and prohibited system account types. In practice, this means you can prove you policy management-level controls on a defined cadence.

Why it matters

SP 800-53 is the catalogue every U.S. federal authorisation (FedRAMP, FISMA, CMMC) and most regulated industries point at. A missing control surfaces as a Plan of Action & Milestones (POA&M) item that an Authorizing Official must approve before the Authority To Operate is granted or renewed.

This control is rated high. Auditors expect a named owner, a remediation SLA, and a tooling artefact that evidences continuous operation.

What an auditor looks for

A 3PAO (FedRAMP) or Independent Assessor (NIST RMF) tests against NIST SP 800-53A assessment procedures. For each control they expect a documented implementation that addresses every assessment objective (Examine, Interview, Test) and an implementation summary in the System Security Plan.

Within Access Control, the assessor will trace your implementation back to the catalogue reference (Control AC-2) and look for objective evidence on the latest two assessment cycles.

How to implement

Logging Monitoring

AWS. Org-trail CloudTrail to a central log archive account, GuardDuty in every region, and Security Hub for cross-source correlation.

Azure. Pipe every diagnostic setting into a central Log Analytics workspace; onboard Microsoft Sentinel for SIEM/SOAR.

GCP. Aggregate audit logs in a dedicated logging project with sink to BigQuery; enable Security Command Center Premium and route findings to Chronicle SIEM.

Operational checklist

Policy. Document the trigger, the owner and the cadence.
Account. Document the trigger, the owner and the cadence.
Usage. Document the trigger, the owner and the cadence.
Access. Document the trigger, the owner and the cadence.
Authorize. Document the trigger, the owner and the cadence.
Scope: management, accounts, attributes, account management, authorization, access control, system, personnel.

Evidence to collect

Identity Scan. IAM / IdP exports — Entra ID, Okta, IAM Identity Center, Workspace directory — showing accounts, roles, MFA state and last sign-in.
Policy Document. A signed and version-controlled policy / standard / procedure document.

Identity analytics (Okta, SailPoint, Access Analyzer) demonstrates least-privilege. Signed policy or standard documents the safeguard. Focus: Account Management.

Common pitfalls

Per-account logging that nobody stitches together at the org level — incidents that cross accounts go undetected for days.

How it maps to other frameworks

Computed from shared tags, control component and key-operation subjects — handy when you are reconciling controls across an audit.

Related controls in NIST SP 800-53 Rev. 5

References

NIST Computer Security Resource Center — NIST SP 800-53 Rev. 5
Catalogue identifier: Control AC-2

Topics: governance riskidentity accessidentity managementaccess reviewprivileged accesslogging monitoring

NIST SP 800-53 Rev. 5 AC-2 — Account Management