fix(auth): return 403 for admin-only route denials

Denying a non-admin an admin-only management route raised a bare Exception,
which the auth error handler maps to 401 and the Prometheus failure metric
records as exception_status="None". The key is valid and re-authenticating
does not help, so the correct status is 403.

Raising HTTPException with 403 fixes both symptoms at once, because the
failure hook reads status_code off the original exception. Every comparable
admin denial in the codebase already returns 403.

litellm/proxy/auth/route_checks.py

@@ -226,17 +226,14 @@ class RouteChecks:
             route (str): The route being accessed
 
         Raises:
-            Exception: With user role and masked user_id information
+            HTTPException: 403, with user role and masked user_id information
         """
-        user_role = "unknown"
-        user_id = "unknown"
-        if user_obj is not None:
-            user_role = user_obj.user_role or "unknown"
-            user_id = user_obj.user_id or "unknown"
-
+        user_role: Final = (user_obj.user_role if user_obj is not None else None) or "unknown"
+        user_id: Final = (user_obj.user_id if user_obj is not None else None) or "unknown"
         masked_user_id: Final = RouteChecks._mask_user_id(user_id)
-        raise Exception(
-            f"Only proxy admin can be used to generate, delete, update info for new keys/users/teams. Route={route}. Your role={user_role}. Your user_id={masked_user_id}"
+        raise HTTPException(
+            status_code=status.HTTP_403_FORBIDDEN,
+            detail=f"Only proxy admin can be used to generate, delete, update info for new keys/users/teams. Route={route}. Your role={user_role}. Your user_id={masked_user_id}",
         )
 
     @staticmethod

tests/test_litellm/proxy/auth/test_route_checks.py

@@ -61,6 +61,43 @@ def test_non_admin_config_update_route_rejected():
     assert "Your role=internal_user" in str(exc_info.value)
 
 
+@pytest.mark.parametrize(
+    "route",
+    ["/policies/list", "/prompts/list", "/in_product_nudges", "/config/update"],
+)
+def test_admin_only_route_denial_is_forbidden_and_carries_status(route):
+    """A valid non-admin key denied an admin-only route is an authorization
+    failure, so it must surface as 403 and carry the status code the metrics
+    layer reads, not an unlabelled 401.
+
+    Regression test for https://github.com/BerriAI/litellm/issues/37108
+    """
+    user_obj = LiteLLM_UserTable(
+        user_id="test_user",
+        user_email="test@example.com",
+        user_role=LitellmUserRoles.INTERNAL_USER.value,
+    )
+    valid_token = UserAPIKeyAuth(
+        user_id="test_user",
+        user_role=LitellmUserRoles.INTERNAL_USER.value,
+    )
+    request = MagicMock(spec=Request)
+    request.query_params = {}
+
+    with pytest.raises(HTTPException) as exc_info:
+        RouteChecks.non_proxy_admin_allowed_routes_check(
+            user_obj=user_obj,
+            _user_role=LitellmUserRoles.INTERNAL_USER.value,
+            route=route,
+            request=request,
+            valid_token=valid_token,
+            request_data={},
+        )
+
+    assert exc_info.value.status_code == 403
+    assert f"Route={route}" in str(exc_info.value.detail)
+
+
 @pytest.mark.parametrize(
     "role",
     [