Security teams should use DSPM to identify where sensitive data lives, then combine that visibility with access reviews to judge whether permissions are justified. In Microsoft 365, a clean entitlement list is not enough if the data is misclassified, over-shared, or sitting in a location with broad inheritance. The practical goal is to review access against actual exposure, not directory structure.
Why This Matters for Security Teams
Microsoft 365 access reviews are useful, but they only answer who has been granted access. DSPM answers a different question: where sensitive data actually lives, how broadly it is exposed, and whether that exposure matches business need. Without DSPM, teams can certify access that is technically valid while ignoring misclassified sites, inherited permissions, shared links, and oversharing that make the real risk much larger.
This matters because M365 exposure often spreads across SharePoint, OneDrive, Teams, and mailboxes in ways that are not obvious from the directory alone. NHI Management Group’s Ultimate Guide to NHIs shows how often organisations miss the underlying exposure layer when identity data is viewed in isolation. The same blind spot appears in M365 reviews: entitlement hygiene is not the same as data hygiene. The OWASP Non-Human Identity Top 10 is a reminder that access decisions fail fastest when teams assume the identity layer tells the full story. In practice, many security teams discover overexposure only after a review cycle has already certified access that should have been challenged.
How It Works in Practice
The practical model is to use DSPM as the discovery and risk-scoring layer, then use Microsoft 365 access reviews as the attestation mechanism. DSPM identifies sensitive data sets, their labels, their locations, and the paths by which they are reachable. Access reviews then test whether the people, groups, guests, and service identities with access to those locations still need it. This creates a review based on actual exposure, not just ownership or group membership.
Start by mapping high-risk repositories and collaboration spaces, especially those with inheritance, guest access, or broad sharing permissions. Then segment reviews by risk instead of volume. A finance SharePoint site with regulated data should be reviewed more aggressively than a low-sensitivity team workspace. If DSPM shows a site contains sensitive data but access is inherited through a parent group, the review should challenge the inherited entitlement, not just the named users. This is also where identity governance and data governance meet: access review owners need enough context to decide whether a permission is justified, and DSPM provides that context.
For stronger outcomes, pair the review with clear decision rules:
- Certify access only when the business purpose matches the data sensitivity.
- Revoke access when the location is sensitive and the requester has no current need.
- Escalate shared links, external guests, and broad groups for manual review.
- Recheck after remediation, because a clean review does not fix mislabelled or overshared data.
Current guidance suggests treating DSPM findings as the risk input and Microsoft 365 reviews as the control action, rather than running them as separate hygiene exercises. For implementation patterns, the NHI Lifecycle Management Guide is useful for thinking about ownership, review cadence, and revocation discipline across digital identities. These controls tend to break down when labels are inconsistent across tenants because reviewers lose confidence in which locations are truly sensitive.
Common Variations and Edge Cases
Tighter review scope often increases administrative overhead, requiring organisations to balance precision against reviewer fatigue. That tradeoff is real: if every access review includes full DSPM context, the process can become slower, but if it does not, the review risks becoming a box-ticking exercise.
There is no universal standard for this yet, but best practice is evolving around risk-based review tiers. High-sensitivity data should drive short review windows, stronger approver requirements, and lower tolerance for inherited access. Lower-sensitivity areas can stay on standard cadences. External collaboration is a common edge case: guest access may be legitimate, but broad sharing and stale links often outlive the original business need. Another edge case is service accounts and automation identities. These are not typically covered well by human-focused access reviews, yet they can still reach sensitive content indirectly through app permissions, Graph access, or delegated workflows.
NHI Management Group has documented how often organisations miss the hidden access layer in its Key Challenges and Risks research, which is relevant here because M365 exposure frequently includes both human and non-human paths. The main operational lesson is simple: if DSPM shows the data is exposed more broadly than the access list suggests, the review outcome should challenge the exposure source, not just the person attached to it.
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 address the attack and risk surface, while NIST CSF 2.0 and NIST AI RMF set the governance and control requirements practitioners need to meet.
| Framework | Control / Reference | Relevance |
|---|---|---|
| OWASP Non-Human Identity Top 10 | NHI-03 | Access review gaps often hide over-privileged digital identities. |
| NIST CSF 2.0 | PR.AC-4 | Least-privilege review depends on knowing what data is actually exposed. |
| NIST AI RMF | GOVERN | Risk decisions need ownership, context, and accountability across data and identity. |
Use DSPM findings to challenge excessive access and remove unnecessary permissions during each review cycle.
Related resources from NHI Mgmt Group
Deepen Your Knowledge
Reviewed and updated by the NHIMG editorial team on June 10, 2026.
NHI Mgmt Group — the #1 independent authority on Non-Human Identity, IAM, and Agentic AI security. nhimg.org
