Access Control Identity Audit

Access Control Identity Audit

Overview

This skill performs identity and access management (IAM) audits mapped to:

• SOC 2 CC6.1–CC6.8: logical access, credential management, access removal
• HIPAA §164.312(a)(1): access control implementation specifications
• PCI-DSS Req 7: restrict access to CHD by business need-to-know
• PCI-DSS Req 8: identify and authenticate users

AI agent deployments introduce non-human identities: MCP service accounts, LLM API keys, agent runtime roles, and deanonymization tools. These require the same rigor as human admin accounts.

When to Use

Use this skill when:

• Quarterly access reviews or SOC 2 CC6.2/CC6.3 evidence collection
• Auditing cloud IAM (AWS IAM, Azure RBAC, GCP IAM) for least privilege
• Reviewing MCP OAuth scopes and agent tool permissions
• Joiner-mover-leaver (JML) process validation
• MFA coverage assessment for privileged and ePHI/CDE access
• Investigating ** excessive permissions** on service accounts running agents

Do not use this skill when:

• Network segmentation and firewall rules (use pci-dss-network-segmentation)
• BAA legal review (use hipaa-baa-vendor-assessment)
• Log integrity architecture (use audit-logging-integrity)

Core Process

Execute steps in order.

Step 1: Identity inventory

1. Export all identities from authoritative IdP and cloud IAM:
   • Human users, groups, roles
   • Service accounts, API keys, OAuth clients (MCP, agent, CI/CD)
2. Classify each identity:
   • Human standard, Human privileged, Non-human service, Emergency break-glass
3. Tag data access scope: ePHI, CHD, Confidential, Public
4. Artifact: identity-inventory-{id}.csv.

Step 2: SOC 2 CC6 mapping

Document PASS/FAIL per criterion with evidence source.

Step 3: Least privilege analysis

For each identity with ePHI, CHD, or admin access:

1. Export effective permissions (policy simulation, IAM analyzer).
2. Compare to role baseline (intended permission set).
3. Flag:
   • * actions on * resources
   • Unused permissions (90-day access advisor idle)
   • Direct user policies instead of group/role-based access
   • Shared API keys across multiple services
4. Severity: CRITICAL for CDE/PHI over-permission; HIGH for admin; MEDIUM for stale access.

Step 4: MFA and authentication (PCI Req 8, HIPAA §164.312(d))

1. Verify MFA enforced for:
   • All privileged human accounts
   • Remote access to CDE/ePHI systems
   • Agent admin consoles and deanonymization functions
2. Verify service accounts use key rotation, short-lived tokens, or workload identity—not long-lived static keys in repos.
3. Test: password-only login to privileged console must fail.

Step 5: MCP and agent-specific access

1. Inventory MCP server credentials:
   • OAuth clients: scopes, redirect URIs, PKCE requirement
   • Postgres MCP: DB roles, read-only vs write, schema limits
   • Playwright MCP: target URL allowlist, no arbitrary navigation
2. Inventory agent tools:
   • deanonymize_response: restricted to authorized roles
   • redaction_status: read-only, logged
3. Verify no shared agent runtime credential across prod and dev.

Step 6: Joiner-mover-leaver validation

1. Sample HR-triggered access tickets (hire, transfer, terminate) from examination period.
2. Verify:
   • Provisioning within SLA with manager approval
   • Transfer: old permissions removed within SLA
   • Termination: same-day disable of all accounts and API keys
3. FAIL if terminated user retains MCP or cloud access.

Step 7: Access certification (recertification)

1. Run quarterly certification campaign:
   • Managers attest direct reports' access
   • Service account owners attest non-human identities
2. Export certification completion rate; unreviewed accounts → revoke or escalate.
3. Store signed attestation for soc2-evidence-collection.

Step 8: Remediation and evidence

1. Remediation priorities: CRITICAL revoked within 24h, HIGH within 7 days.
2. Package: IAM exports, MFA report, JML samples, certification exports, hashes.

Common Rationalizations

Red Flags

• Terminated employee active in IAM or MCP OAuth sessions
• Deanonymization tool callable without role check
• Postgres MCP service account has SUPERUSER or write on PHI/CDE tables
• MFA optional for cloud root/admin accounts
• Shared long-lived API key for agent and CI pipeline
• Access certification completion below 95% with no revocation follow-up
• Break-glass account used without post-use review log entry

Verification

• Complete identity inventory with human/non-human classification
• CC6.1–CC6.8 assessed with PASS/FAIL and evidence per criterion
• Least privilege analysis completed with over-permission findings prioritized
• MFA enforced and tested for all privileged and remote access paths
• MCP OAuth scopes and agent tool permissions documented and restricted
• JML sample validated with timely deprovisioning evidence
• Quarterly access certification completed or gaps flagged with revocation plan
• CRITICAL findings remediated or under emergency exception with expiry
• Evidence exports hashed and mapped to control IDs
• Service account key rotation policy verified (no stale keys >90 days)