Secure Legacy Applications with Entra ID and Datawiza Access Proxy

Legacy applications keep critical business processes running—but they’re often the hardest to secure. Many were built before modern SSO and MFA became standard, and changing them can be risky, expensive, or simply not feasible (vendor-managed apps, end-of-life stacks, limited test coverage).

If you’re standardizing on Microsoft Entra ID and need to secure legacy web applications without rewriting code, Datawiza Access Proxy provides a practical approach: put Entra ID in front of the app, enforce modern policies, and keep the legacy system intact.

Why legacy apps are still a security gap

For IT and security admins, legacy apps create familiar problems:

• No native support (or unreliable support) for SAML, OIDC, or modern auth standards
• Hard-coded or proprietary login flows that are difficult to change
• Inconsistent authentication across the app portfolio
• Limited maintenance windows—auth changes can break production access
• Pressure to enforce MFA and Conditional Access consistently across all apps

Legacy apps are frequently the “last mile” preventing identity standardization.

What is Datawiza Access Proxy?

Datawiza Access Proxy (DAP) is an authentication and access layer that sits in front of your application. It enables modern SSO and policy enforcement without requiring application rewrites or intrusive changes to the app.

With Datawiza, you can:

• Add Microsoft Entra ID SSO to legacy web applications
• Enforce MFA and Conditional Access via Entra ID
• Centralize access policies across many legacy apps
• Reduce risk while minimizing disruption to business-critical systems

How Entra ID + Datawiza works for legacy apps

A typical flow looks like this:

1. Users access the legacy app URL (internal or external).
2. Datawiza Access Proxy intercepts the request.
3. Users authenticate with Microsoft Entra ID.
4. Entra ID applies security policies (Conditional Access, MFA, sign-in risk checks, device requirements, location rules).
5. Datawiza forwards the user to the legacy app after successful authentication.

Result: the legacy app stays the same, while access becomes modern, consistent, and centrally governed.

What types of legacy apps can this secure?

Datawiza is commonly used to protect legacy and on-prem web applications such as:

• Internal portals and intranet apps
• ERP and finance portals (e.g., Oracle EBS modules, older SAP web UIs)
• Supplier/vendor/partner portals built years ago
• Custom line-of-business apps tied to older stacks (IIS/Java/Tomcat, etc.)

If you have a long tail of business-critical applications you can’t easily modify, this approach is built for that reality.

Why not just modernize the legacy app?

Sometimes modernization is the right end goal. But in many environments, modernization projects take months (or years), require deep testing, and create change risk—especially when the legacy app is fragile and business-critical.

Datawiza is designed for cases where you need stronger security now, while modernization remains a longer-term plan.

Key benefits: secure legacy apps with Entra ID without rewriting

1) Entra ID SSO for legacy applications

Even if your legacy app can’t natively integrate with Entra ID, Datawiza adds an authentication layer so you can enable Entra ID SSO for legacy apps without modifying application code.

2) Enforce MFA and Conditional Access consistently

Once the app is protected by Entra ID through Datawiza, you can apply policies such as:

• Require MFA for all users (or only for high-risk sign-ins)
• Require compliant devices or block unmanaged access
• Restrict by geography, network, or sign-in risk
• Apply different rules for employees vs contractors vs partners

This helps standardize controls across both modern SaaS apps and older internal systems.

3) Reduce credential and access risk

Legacy apps often rely on weaker authentication patterns and inconsistent controls. Standardizing sign-in through Entra ID reduces exposure from password reuse, weak MFA coverage, and legacy access paths.

4) Faster rollout across many applications

Instead of building or troubleshooting a custom identity integration per application, Datawiza helps you onboard legacy apps in a repeatable way—especially valuable when you have dozens of legacy systems to secure.

Why not Microsoft Entra App Proxy for some legacy apps?

Microsoft Entra App Proxy can work well in many deployments. However, in some architectures it introduces a cloud transit path for application access.

With Datawiza Access Proxy, you can deploy the proxy inside your network, so application traffic stays internal—while Microsoft Entra ID still provides cloud-based authentication and policy enforcement (MFA / Conditional Access).

Want a deeper comparison? Read: https://www.datawiza.com/blog/industry/an-alternative-to-entra-app-proxy/

Get started: protect legacy apps with Entra ID

If you need to secure legacy applications with Microsoft Entra ID—without rewriting apps—Datawiza Access Proxyhelps you deploy modern SSO and MFA quickly and safely.

Book a demo to see how Datawiza can protect your legacy app portfolio and accelerate your identity modernization plan.

FAQ

Does this require changes to the legacy application? In most cases, no. Datawiza sits in front of the app to enforce Entra ID authentication and policy controls without requiring application code changes.

Can we enforce Entra Conditional Access and MFA on legacy apps? Yes. Because users authenticate through Entra ID, you can apply Conditional Access policies such as MFA, device compliance, sign-in risk, location restrictions, and group-based access.

How does this impact the user experience? Users get a consistent Entra ID sign-in experience across applications. After authentication, they are routed to the legacy app normally—without needing separate passwords or a new login method per app.

What’s required on the network side? You’ll need a routing approach to place Datawiza in front of the app (for example, DNS cutover, load balancer, reverse proxy, or gateway routing). Datawiza is deployed in your environment so you can align with internal network and security requirements.

How do we roll this out across many legacy apps? Most teams start with a PoC on one or two high-value apps, then onboard additional applications using the same pattern. This “app-by-app” rollout reduces risk and avoids big-bang changes.