fix: enforce API key endpoint restrictions at the auth layer, not middleware (#23637)

The APIKeyRestrictionMiddleware only inspected the Authorization header for sk- tokens, but get_current_user also reads API keys from cookies and x-api-key headers. This allowed complete bypass of endpoint restrictions by sending the key via an alternate transport.

Moves the restriction check into get_current_user_by_api_key so it runs regardless of how the API key was delivered. Removes the now-redundant middleware.

backend/open_webui/utils/auth.py

@@ -427,6 +427,26 @@ async def get_current_user_by_api_key(request, api_key: str):
     ):
         raise HTTPException(status.HTTP_403_FORBIDDEN, detail=ERROR_MESSAGES.API_KEY_NOT_ALLOWED)
 
+    # Enforce endpoint restrictions — checked here (not in middleware)
+    # so it applies regardless of how the API key was transported
+    # (Authorization header, cookie, x-api-key header, etc.).
+    if request.app.state.config.ENABLE_API_KEYS_ENDPOINT_RESTRICTIONS:
+        allowed_paths = [
+            path.strip()
+            for path in str(request.app.state.config.API_KEYS_ALLOWED_ENDPOINTS).split(',')
+            if path.strip()
+        ]
+        request_path = request.url.path
+        is_allowed = any(
+            request_path == allowed or request_path.startswith(allowed + '/')
+            for allowed in allowed_paths
+        )
+        if not is_allowed:
+            raise HTTPException(
+                status_code=status.HTTP_403_FORBIDDEN,
+                detail=ERROR_MESSAGES.ACCESS_PROHIBITED,
+            )
+
     # Add user info to current span
     if ENABLE_OTEL:
         from opentelemetry import trace