I. Overview

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flowchart LR
    A["Manually tracked, drifting\ncloud accounts"] -- "Need for continuous\nposture visibility" --> B["Formal Cloud Access\nControl Matrix"]
    style A fill:#f9f9f9,stroke:#333,stroke-width:3px
    style B fill:#e1f5fe,stroke:#01579b,stroke-width:3px

Definition: A Cloud Access Control Matrix is a structured inventory of every identity — human user, group, or service account — with access to a cloud account, subscription, or project, together with the role, permission scope, and resource boundary each identity holds.

Features:
( Ownership ) Maintained by the cloud security or platform engineering team in coordination with resource owners.
( Multi-Cloud Scope ) Extends the traditional access matrix concept into environments where identities span multiple providers, cross-account roles, and machine-to-machine service accounts.
( Least Privilege Verification ) Confirms whether privileged cloud access matches job function.
( Stale Grant Detection ) Surfaces stale grants and orphaned service accounts that would otherwise remain active.

II. Structure & Process

sequenceDiagram
    participant Requester as "Requesting Team"
    participant Owner as "Resource/Account Owner"
    participant CloudSec as "Cloud Security/IAM Team"
    participant Auditor as "Internal Audit"

    Requester->>Owner: "Request cloud role or service account access"
    Owner->>CloudSec: "Approve and specify permission scope"
    CloudSec->>CloudSec: "Provision access via IaC and update matrix"
    CloudSec->>Owner: "Send matrix for periodic recertification"
    Owner->>Auditor: "Provide matrix as posture review evidence"
FieldDescription
Cloud Account/SubscriptionThe specific account, project, or subscription the entry applies to.
Identity TypeHuman user, group, federated identity, or service/machine account.
Role/Policy NameThe IAM role or managed policy assigned.
Permission ScopeActions permitted, e.g. read-only, contributor, administrator.
Resource ScopeBoundary of the grant, e.g. specific resource group, tag, or account-wide.
MFA EnforcedWhether multi-factor authentication is required for this identity.
Business JustificationWhy this identity requires this level of cloud access.
ApproverResource owner or cloud security lead who authorized the grant.
Last Review DateDate of the most recent access recertification.

The matrix is updated whenever a role, policy, or service account is provisioned or changed, and undergoes full recertification on a fixed cadence — typically monthly for administrative and cross-account roles, and quarterly for standard access — with resource owners attesting each entry is still required.

III. Best Practices & Comparison

DocumentPrimary PurposeUpdate CadenceOwner
Cloud Access Control MatrixTrack which identities can act on which cloud resourcesContinuous, with periodic recertificationCloud security/IAM team, resource owners
Cloud Asset Inventory TrackerTrack which resources exist and who owns themContinuous, discovery-drivenCloud platform team
Cloud Security Configuration BaselineDefine the hardened settings resources must meetVersion-controlled, updated per provider changesCloud security architecture team
  • Grant access through roles or groups defined as code, not one-off console changes.
  • Require MFA and just-in-time elevation for any administrative or cross-account role.
  • Recertify service accounts and machine identities as rigorously as human accounts — they rarely expire on their own.
  • Tie every grant to a documented business justification and a named approver.
  • Cross-reference entries against the Cloud Asset Inventory Tracker so access scope never outlives the resource it was granted for.

Related: Cloud Asset Inventory Tracker, Cloud Security Configuration Baseline.

Last updated 18 Aug 2026, 00:00 UTC. history