They should treat third-party access like a lifecycle-managed identity relationship, not a one-time vendor approval. That means reviewing supplier accounts, delegated admins, and connected services alongside internal users, then revoking access when the business relationship or service need ends. If offboarding is missing, compliance evidence and real access state will diverge.
What compliance reviews should actually verify in third-party SaaS access
Compliance review is not just a vendor questionnaire. The useful check is whether third-party SaaS access still matches an approved business purpose, a named owner, a current contract or service need, and an enforceable offboarding path. That means reviewing supplier users, delegated administrators, API connections, and support access as separate access relationships, not one combined “vendor account” bucket.
A review is strongest when it compares policy intent to live entitlement state. If the vendor can still authenticate after the service ends, or if a dormant integration can still reach sensitive data, the control has failed even if the annual review was signed off on time.
One practical example is Third-Party, B2B and Contractor Access Guide, which treats sponsor ownership, time limits, least privilege, and offboarding as the core of third-party access governance. For organisations reviewing SaaS access, that is the right model: review who has access, why they have it, and what removes it.
Why third-party SaaS access drifts out of compliance
Third-party SaaS access drifts because the approval event and the access lifecycle are often separated by months or years. Vendors change staff, integrations expand, support teams add temporary permissions, and no one revisits the original justification. Over time, compliance records can show an approved relationship while the live system contains broader, older, or inherited access.
This is especially common with delegated admin rights, OAuth-connected apps, shared support accounts, and “break glass” access that was never retired. A good review therefore asks whether the access is still tied to a current service obligation, whether the permissions are still minimal, and whether the organisation can actually revoke them when the contract or use case ends.
For lifecycle discipline, NHI Lifecycle Management Guide is directly relevant because the same provision, rotation, and offboarding logic applies to third-party SaaS connections. The point is not the label on the identity, it is whether the access can be discovered, owned, reviewed, and removed before it becomes residual exposure.
How to evidence control effectiveness during the review
Auditors and internal reviewers usually need more than a list of approved vendors. They need evidence that the organisation can reconcile access approvals to the actual SaaS estate. The strongest evidence is a current inventory of third-party users, privileged roles, service connections, and token-based integrations, paired with dated review decisions and revocation records.
When the environment uses connected apps or federated access, the review should also check whether access is audience-scoped, time-bounded, and attributable to a named owner. If the supplier cannot explain each live permission or if the organisation cannot produce a clean removal record, the control should be treated as incomplete, not merely documented.
At a broader governance level, Access Reviews and Certification Guide is useful because it focuses on closed-loop remediation, not rubber-stamped certification. That is the right standard for third-party SaaS: the review must produce actual entitlement change, not just compliance evidence.
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 surface, NIST SP 800-53 Rev 5 and CIS Controls v8 set the technical controls, and ISO/IEC 27001:2022 defines the regulatory obligations.
| Framework | Control / Reference | Relevance |
|---|---|---|
| NIST SP 800-53 Rev 5 | AC-2 — Account Management | Third-party SaaS access is governed through account provisioning, review, and timely removal. |
| IA-5 — Authenticator Management | SaaS integrations often rely on tokens, keys, and credentials that must be rotated and revoked. | |
| Recommendation — Review supplier accounts and revoke any access no longer tied to an approved business need. Track and retire third-party authenticators, tokens, and keys when the service need ends. | ||
| ISO/IEC 27001:2022 | A.5.18 — Access rights | Third-party SaaS access reviews must confirm rights are approved, current, and removed when no longer needed. |
| Recommendation — Periodically review and remove third-party access rights that no longer have a valid need. | ||
| CIS Controls v8 | CIS-6 — Access Control Management | The topic is about governing and removing vendor access as part of access control management. |
| Recommendation — Enforce least privilege and timely revocation for all third-party SaaS access paths. | ||
| OWASP Non-Human Identity Top 10 | NHI-01 — Improper Offboarding | The answer centers on ending third-party access cleanly when the business relationship ends. |
| NHI-05 — Overprivileged NHI | Supplier SaaS accounts and integrations are often left with excess privilege beyond the review scope. | |
| NHI-07 — Long-Lived Secrets | Third-party SaaS often uses API keys and tokens that persist beyond the intended service period. | |
| Recommendation — Remove third-party accounts, tokens, and delegated access immediately when offboarding triggers. Reduce third-party SaaS permissions to the minimum required for the approved use case. Rotate or expire third-party secrets instead of leaving them valid indefinitely. | ||
| OWASP API Security Top 10 | API2 — Broken Authentication | Connected SaaS services often authenticate with tokens or keys that must be verified and revoked correctly. |
| API5 — Broken Function Level Authorization | Delegated admin and support access can exceed the functions a third party should perform. | |
| Recommendation — Validate and revoke third-party API authentication paths when vendor access is no longer required. Constrain third-party accounts so they can only use the functions explicitly approved. | ||
Practitioner Guidance
What to prioritise: Start with third parties that have production data access, delegated administrative rights, or non-expiring API tokens. Those are the relationships most likely to create both compliance gaps and real breach exposure if they are left untouched.
Decision rule: If the third-party access cannot be tied to a current business owner and a revocation path, treat it as an exception requiring immediate remediation. If the access is justified but still broad, narrow it before the next certification cycle rather than waiting for annual review.
What to verify: Confirm that every supplier account, integration, and support path has an owner, an expiry or review date, and an offboarding trigger. The review is only credible when the system state matches the paperwork.
Practitioner takeaway: The control objective is to make third-party SaaS access lifecycle-managed and revocable, because compliance evidence without actual offboarding is just documentation drift.
Related resources from NHI Mgmt Group
- How should organisations handle third-party access when collaboration must stay open but compliance risk is rising?
- When should organisations treat third-party SaaS access as privileged access?
- How should security teams handle third-party access when vendors and SaaS tools are part of the attack path?
- What breaks when organisations leave third-party access standing during geopolitical escalation?