Look for explicit source binding, narrow service scope and evidence that the service cannot be redirected into broader action than intended. If the service can be triggered across tenants or extended through transitive permissions, the organisation needs tighter policy conditions and stronger monitoring of delegated activity.
How to tell whether delegated action is tightly bounded
The first thing to look for is whether the cloud service is acting under a clearly defined delegation, not under open-ended authority. A safe design usually binds the action to a specific source, specific tenant or account, and a specific purpose. If the service can operate without those constraints, you are no longer just reviewing delegation, you are reviewing an expandability problem.
That means security teams should check whether the service’s authority is explicitly scoped to the intended workflow, whether the request can be traced back to a known origin, and whether the downstream action remains limited to the original principal’s intent. This is where delegation standards matter, and RFC 8693: OAuth 2.0 Token Exchange is a useful reference point for understanding controlled token exchange and on-behalf-of flows.
A service that can act “for” another principal should not be able to reissue that authority broadly, reuse it in unrelated contexts, or convert a narrow permission into a much wider one through chained calls. The core question is not just whether the service is authenticated, but whether its delegated authority is still mechanically constrained after handoff.
Where transitive permissions become the real exposure
The highest-risk failure mode is transitive permission growth, where a service starts with a narrow mandate but can reach additional systems, tenants, or data paths through inheritance, forwarding, or hidden trust relationships. That is especially important when the service can be triggered across tenants, because cross-boundary execution can turn a local control issue into a broader trust failure.
Security teams should examine whether the service can be redirected into actions that were never intended by the original granting principal. If one delegated permission unlocks another, or if a downstream service treats the first service as fully trusted, the practical privilege can exceed the formal grant. NHIMG’s Cloud Workload Identity Guide is a strong companion for understanding how temporary credentials, federation, and cloud trust boundaries can either contain or expand that exposure.
Policy conditions matter here because they define where delegation is allowed, under what context, and with what limits. When those conditions are too broad, the service may technically be “working as designed” while still being able to act outside the intended security boundary.
What monitoring should prove about delegated activity
Good monitoring should show more than that the service was active. It should show who or what caused the action, which principal’s authority was used, which resource was targeted, and whether the resulting behaviour stayed inside the approved scope. If you cannot reconstruct those points from logs, delegated action is effectively opaque.
Teams should also look for signs that delegated activity is being reused in unexpected ways, such as repeated cross-tenant invocation, unusual target expansion, or access to resources that sit outside the service’s normal operating pattern. For cloud services and service principal in particular, Azure RBAC and Service Principals Guide is relevant because role scope, assignment conditions, and ownership boundaries directly affect whether delegation stays narrow.
When delegation is weakly observed, investigators often have to infer abuse after the fact from resource use or data movement. That is too late for many environments, so the better test is whether the control plane can already distinguish intended delegation from unexpected privilege extension.
Risk and Threat Considerations
Delegated cloud action becomes risky when the service can be repurposed, redirected, or allowed to fan out beyond the original principal’s intent. The concern is not only overuse of access, but trust abuse through cross-tenant execution, transitive permissions, and weak source binding.
Failure mechanism: An attacker, or simply a misconfigured integration, exploits a loosely bound delegation path so the service can act with broader authority than intended, including in adjacent tenants or downstream systems.
Impact: The organisation can lose control over who really authorised the action, expand the blast radius of a compromise, and create hard-to-detect access paths that look legitimate in logs.
Standards & Framework Alignment
This section maps relevant standards and security frameworks to the operational risks and controls described in this guidance.
OWASP Non-Human Identity Top 10 and OWASP API Security Top 10 address the attack and risk surface, while NIST SP 800-53 Rev 5 and NIST Zero Trust (SP 800-207) set the governance and control requirements practitioners need to meet.
| Framework | Control / Reference | Relevance |
|---|---|---|
| NIST SP 800-53 Rev 5 | IA-9 — Service Identification and Authentication | Delegated service action depends on service-to-service trust and scoped authentication. |
| AC-6 — Least Privilege | The question centers on narrow service scope and preventing broader-than-intended action. | |
| AU-2 — Event Logging | Monitoring delegated activity requires auditable records of who acted, where, and under what authority. | |
| Recommendation — Use IA-9 to authenticate services with scope and binding that limit delegated use. Apply AC-6 to restrict delegated service permissions to the minimum necessary scope. Use AU-2 to ensure delegated actions are recorded with enough detail for traceability. | ||
| NIST Zero Trust (SP 800-207) | AC-6 — Least Privilege Access | Delegated cloud services should be continuously constrained rather than trusted broadly. |
| Recommendation — Apply least-privilege access so delegated services cannot exceed their intended function. | ||
| OWASP Non-Human Identity Top 10 | NHI-05 — Overprivileged NHI | A service acting for another principal can become dangerous when its authority expands beyond necessity. |
| NHI-08 — Environment Isolation | Cross-tenant triggering and boundary crossing are isolation failures for delegated service identities. | |
| NHI-09 — NHI Reuse | Redirectable or shared delegation paths can let one trust path be reused for broader action. | |
| Recommendation — Review delegated service permissions and remove any privilege that exceeds the workflow need. Enforce isolation so delegated activity cannot cross environments or tenants without explicit approval. Prevent reuse of delegated credentials or trust paths across unrelated tenants and workflows. | ||
| OWASP API Security Top 10 | API5 — Broken Function Level Authorization | The issue includes whether a service can perform actions beyond the function it was meant to execute. |
| API6 — Unrestricted Access to Sensitive Business Flows | If delegated services can be redirected, they may reach sensitive workflows beyond the intended path. | |
| API8 — Security Misconfiguration | Weak policy conditions and broad delegation are often configuration failures rather than code flaws. | |
| Recommendation — Verify that delegated API functions are authorized at the function level, not only at login. Restrict sensitive business flows so delegated calls cannot be repurposed into broader execution. Harden API and policy configuration so delegation cannot be widened by default settings. | ||
Practitioner Guidance
What to verify: Confirm that the delegated action is tied to a specific source principal, a narrow scope, and explicit policy conditions that prevent broader reuse. If the service can act without a stable, auditable source binding, treat that as a design gap rather than a logging gap.
Decision rule: If the service can cross tenant boundaries or inherit extra permissions through chained trust, require tighter conditional policy and separate monitoring for delegated actions, not just for the service itself. If the same delegation pattern would be unacceptable for a human admin session, it is usually too broad for a service principal as well.
Practitioner takeaway: The key judgement is whether delegated cloud action is still bounded by the original principal’s intent after every hop, because once transitive trust is allowed to widen the scope, normal authentication alone no longer tells you who truly has authority.
Related resources from NHI Mgmt Group
- Guide: Agentic AI Identity Guide
- How should security teams prioritise NHI remediation in cloud environments?
- How should security teams govern non-human identities in cloud environments?
- How should security teams govern Active Directory service accounts?
- How should security teams govern non-human identities at scale?
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Reviewed and updated by the NHIMG editorial team on October 22, 2026.
NHI Mgmt Group — the #1 independent authority on Non-Human Identity, IAM, and Agentic AI security. nhimg.org