Microsoft Power Platform — Power Apps, Power Automate, Power BI, and Power Pages — has quietly become one of the most significant shifts in how businesses build internal tools. Thousands of organisations are building apps, workflows, and dashboards without traditional development teams.
But there's a security question that often gets overlooked in the rush to build: how do you make sure only the right people access these tools?
The answer is already built in. And it's enterprise-grade.
How Power Platform Handles Identity
Every Power Platform app runs within a Microsoft 365 / Entra ID (formerly Azure Active Directory) tenant. This means that from day one, your Power App has access to the full Microsoft identity infrastructure:
- Microsoft Entra ID authentication — users log in with their existing Microsoft 365 credentials
- Conditional Access policies — the same rules that protect Outlook and Teams apply to your Power App
- MFA enforcement — if your tenant requires MFA, it's enforced in Power Apps automatically
- Role-based access control — Entra ID security groups and Microsoft 365 groups translate directly into app permissions
You don't need to implement authentication. You inherit it.
Entra ID Groups as App Permissions
One of the most powerful (and underused) features of Power Platform is Entra ID group-based access.
When you share a Power App, you share it with users or groups. That group is managed in Entra ID, which means:
- Add a new employee to the "Kitchen Staff" group in Entra → they automatically get access to your Kitchen Compliance app
- Remove an employee from the group → access is revoked immediately, across all apps that use that group
- No need to manage per-app user lists — your organisational structure drives your app access
For a business with 50+ staff using a dozen internal tools, this is transformative. One authoritative source of truth (Entra ID) drives access to everything.
Conditional Access: The AI Layer
Power Platform apps can be covered by the same Conditional Access policies as the rest of your Microsoft 365 environment. This means:
- Require MFA for external access — staff can use the app seamlessly from the office, but any access from outside the network requires a second factor
- Block access from unmanaged devices — only company-managed devices (enrolled in Intune) can access the app
- Restrict by location — access limited to UK IP ranges only, for example
- Require compliant devices — device health checks before access is granted
These policies are configured once in the Entra portal and applied to your Power Platform environment automatically. No code. No per-app configuration. Your IT admin sets the rules; the platform enforces them.
Power Automate and OAuth: Connecting to External Systems
One of the more nuanced SSO challenges in Power Platform is how Power Automate flows connect to external systems — CRMs, APIs, databases, third-party SaaS tools.
Each connector in Power Automate uses OAuth 2.0 to authenticate with external services. When a user creates or runs a flow, the connections use their identity — not a shared service account — to call external APIs.
This has important implications:
**For security:** Actions in external systems are attributable to individual users, not anonymous service accounts. Your audit trail is clean. **For permissions:** A flow will only be able to do what the running user is allowed to do in the target system. If a user doesn't have write access to a SharePoint list, their flow can't write to it either. **For data governance:** Sensitive data accessed by a flow is subject to the same Microsoft Information Protection policies as everything else in your tenant.Power Pages: SSO for External Portals
Power Pages (formerly Power Portals) extends SSO to external-facing websites — customer portals, partner portals, self-service tools for people outside your organisation.
External users can authenticate via:
- Microsoft Entra External ID — for business partners with Microsoft accounts
- Azure AD B2C — for custom external user directories with branded login experiences
- Social providers — Google, Facebook, LinkedIn via OIDC
- Local authentication — username and password managed in Dataverse (least preferred, but available)
This means you can build a customer-facing portal in Power Pages where your external users authenticate with their existing Google or Microsoft accounts — no new passwords to manage, no user management overhead for your team.
Service Principal Authentication for Unattended Flows
For production automation that runs on a schedule or trigger without a user present (nightly data syncs, report generation, alert systems), running flows under a user account is poor practice. If that user leaves, the flow breaks.
The right approach is an Entra ID Service Principal — a non-human identity specifically for automated processes.
Setup involves:
- Register an app in Entra ID (takes 5 minutes in the Azure portal)
- Grant the app specific Microsoft Graph permissions (only what it needs — principle of least privilege)
- Configure Power Automate to use the service principal for specific connections
- The service principal has its own lifecycle, independent of any human user
This is how enterprise-grade automation handles identity. The flow has its own identity, it has only the permissions it needs, and it can be revoked independently.
What This Means in Practice
For a business in the Microsoft 365 ecosystem, the Power Platform SSO story looks like this:
- Internal staff → log in with existing Microsoft credentials, MFA enforced, group-based access
- External customers/partners → log in via Google/Microsoft/custom IdP through Power Pages
- Automated processes → run under a service principal with scoped permissions
- All access → auditable, governed by Conditional Access, covered by Entra ID's AI-powered risk detection
The only thing it requires is a Microsoft 365 Business subscription (which most businesses already have) and someone who understands how to configure Entra ID properly.
Where We Come In
Power Platform is powerful, but "powerful" and "correctly configured" are not the same thing. A Power App with no Conditional Access policies and sharing set to "anyone in the organisation" is not a secure tool — it's an accident waiting to happen.
We help businesses:
- Audit existing Power Platform environments for security gaps
- Configure Entra ID groups and Conditional Access for Power Platform
- Build custom Power Apps and Automate flows that inherit best-practice identity configuration from day one
- Integrate Power Platform with external systems via properly scoped service principals
If your organisation is using Power Platform and you're not sure whether your apps are properly secured — let's talk.