Fix Insecure API Management in Helidon

Helidon microservices often ship with 'naked' endpoints. Insecure API management in Helidon SE/MP usually manifests as exposed administrative routes, lack of rate limiting, or absent authentication providers. Attackers exploit these to leak metrics, dump heap traces, or hit internal logic. We fix this by enforcing a Security provider and applying RBAC filters directly to the Routing tree.

The Vulnerable Pattern

Routing routing = Routing.builder()
    .get("/api/admin/config", (req, res) -> res.send("DB_PASSWORD=secret")) // Exposed sensitive data
    .get("/metrics", (req, res) -> res.send(getMetrics())) // Unauthenticated internal telemetry
    .build();
WebServer.builder(routing).build().start();

The Secure Implementation

The vulnerability lies in the default 'allow-all' routing strategy. The fix implements Helidon's Security component. First, we register `SecuritySupport` to the routing builder. Then, we apply `SecurityHandler` filters to specific paths. The `.authenticate()` call ensures a valid identity is present, while `.rolesAllowed("ADMIN")` enforces strictly defined Role-Based Access Control (RBAC). For management endpoints like `/metrics`, never expose them to the public internet; bind them to a private interface or wrap them in a dedicated security provider as shown.

Security security = Security.builder()
    .addProvider(HttpBasicAuthProvider.builder().build())
    .build();
Routing routing = Routing.builder()
.register(SecuritySupport.create(security))
.register(“/api”, SecurityHandler.create().authenticate()) // Global auth for API
.get(“/api/admin/config”, SecurityHandler.create().rolesAllowed(“ADMIN”), (req, res) -> res.send(“DB_PASSWORD=secret”))
.get(“/metrics”, SecurityHandler.create().rolesAllowed(“MONITOR”), (req, res) -> res.send(getMetrics()))
.build();
WebServer.builder(routing).build().start();