How should IAM teams use identity graphs to improve access reviews?

IAM teams should use identity graphs to trace how access is inherited, combined and propagated across systems before they certify it. That turns access review from a flat entitlement check into a relationship check, which is essential when permissions come from roles, groups and legacy integrations spread across multiple platforms.

Why identity graphs make access reviews more accurate

Identity graphs help reviewers see access as a connected set of relationships, not just a list of entitlements. That matters because a user or service can inherit access through groups, nested roles, shared accounts, platform links and legacy connectors. Review quality improves when the team can see where access came from, where it flows next, and which connections are really driving effective privilege.

An identity graph also changes the review unit. Instead of asking only whether an individual entitlement looks valid, teams can ask whether the upstream relationship is still valid, whether the access is duplicated elsewhere, and whether multiple paths are producing the same effective permission. That reduces false confidence from clean-looking point-in-time entitlements that still add up to excessive access.

In practice, the graph is most useful when it joins identity data that is otherwise fragmented. A useful starting point is to pair access review data with the underlying identity record, group membership, role model and platform connections so the reviewer can distinguish direct assignment from inherited access. NHIMG’s Identity Data Quality and Identity Fabric Guide is useful here because access review depends on clean correlation and reliable upstream identity data before any certification decision is trustworthy.

How to structure reviews around inherited, combined and propagated access

The best access review design starts by collapsing duplicate pathways into a single reviewable view. If a person reaches the same application through a role, a group and a legacy connector, reviewers should not be asked to certify those three paths independently without context. The graph should surface the effective access, the contributing relationships and the least disruptive removal point.

That means review workflows should distinguish between direct entitlements and derived entitlements. Direct access is often easy to certify or revoke. Derived access is the harder case because revoking one edge can have no effect if another path still grants the same permission. Identity graphs make that distinction visible so the review can focus on the control point that actually changes risk.

For teams building or tuning the operating model, identity governance and role design are the practical companions to graph-based review. NHIMG’s IAM and IGA Basics helps frame the review as an entitlement and governance problem, while the Role Mining and Role Design Guide is helpful when graph analysis shows that role structure, not individual entitlement sprawl, is the root cause of review noise.

What good looks like in a graph-based certification process

A strong process uses the graph to shorten the path from observation to decision. Reviewers should be able to see effective access, upstream source, business owner, and dependency chain in the same workflow, then approve, remove or escalate based on that full context. If the graph only adds reporting richness but does not change the reviewer’s decision path, it is not improving certification in a meaningful way.

The most useful operational outcome is a review that removes access at the relationship level, not just the entitlement level. That is especially important where access is inherited from parent roles or shared infrastructure objects. In those cases, the right action may be to fix the parent relationship, not to repeatedly certify the child permission every cycle.

Teams should also expect the graph to reveal recurring control failures, such as privilege creep, duplicate access paths and ownership gaps. NHIMG’s Access Reviews and Certification Guide is relevant because the review program should be designed to remove access, close the loop on remediation and reduce reviewer fatigue rather than simply document approvals.

Risk and Threat Considerations

Identity graphs reduce blind spots, but they can also expose how quickly excessive privilege accumulates across platforms. If the graph is incomplete, stale or poorly correlated, reviewers may certify access that looks narrow in one system but remains broad through another inherited path. The main risk is not the graph itself, but false assurance from partial visibility.

Failure mechanism: Incomplete identity correlation, stale joins between systems or poor ownership mapping can hide effective access paths, causing reviewers to approve access that still exists through another inherited edge.

Impact: Excessive privilege persists, revocation becomes incomplete, and attacker or insider abuse can move through paths that the review never surfaced.

Standards & Framework Alignment

This section maps relevant standards and security frameworks to the operational risks and controls described in this guidance.

NIST SP 800-53 Rev 5 and NIST CSF 2.0 set the technical controls, while ISO/IEC 27001:2022 defines the regulatory obligations.

Framework	Control / Reference	Relevance
NIST SP 800-53 Rev 5	AC-2 — Account Management	Access reviews depend on account and entitlement review at scale.
	AC-6 — Least Privilege	Identity graphs help identify where effective privilege exceeds what is needed.
	AU-6 — Audit Review, Analysis, and Reporting	Graph-based review depends on analyzing identity and access evidence across systems.
Recommendation — Use AC-2 to review account assignments, disable stale access and confirm ongoing need. Apply AC-6 to remove excess access revealed by inherited or duplicated relationships. Use AU-6 to analyze access evidence and support certification decisions with traceable records.
NIST CSF 2.0	PR.AA-01 — Identity Management, Authentication, and Access Control Policies, Processes, and Procedures	Identity graphs strengthen access governance processes and decision quality.
	ID.AM-01 — Physical Devices and Systems Are Inventoried	Identity graphs rely on accurate inventory of connected systems and sources of access.
Recommendation — Define access review procedures that use identity relationships to validate effective access. Maintain an inventory of systems that feed access relationships into review workflows.
ISO/IEC 27001:2022	A.5.15 — Access control	Graph-based reviews are an access control governance mechanism.
	A.5.16 — Identity management	Identity graphs depend on linking identity records across systems for review accuracy.
	A.5.18 — Access rights	The review process determines whether access rights should remain in force.
Recommendation — Use access control reviews to verify that granted permissions still match business need. Keep identity records correlated so access reviews can assess effective access correctly. Recertify access rights against current role, ownership and business justification.

Practitioner Guidance

What to verify: Validate that the graph shows effective access, not just direct entitlements. If a reviewer cannot see inherited access, duplicate pathways and the upstream source of authority, the certification result is too weak to trust.

What to prioritise: Start with high-risk populations and relationship-heavy systems, especially where roles, group nesting or legacy integrations create hidden privilege accumulation. Those are the places where graph context changes outcomes most.

Common mistake: Do not use the graph only as a reporting layer. If it does not change what gets certified, what gets removed, or where ownership is assigned, it is adding complexity without improving control.

Practitioner takeaway: The value of an identity graph in access review is measured by how well it exposes the real source of effective access, then lets teams remove privilege at that source instead of certifying symptoms.