diff --git a/src/node/app/server.tsx b/src/node/app/server.tsx
index a2e55033..b14876e6 100644
--- a/src/node/app/server.tsx
+++ b/src/node/app/server.tsx
@@ -3,6 +3,7 @@ import * as http from "http"
 import * as React from "react"
 import * as ReactDOMServer from "react-dom/server"
 import App from "../../browser/app"
+import { HttpCode, HttpError } from "../../common/http"
 import { Options } from "../../common/util"
 import { HttpProvider, HttpResponse, Route } from "../http"
 
@@ -21,6 +22,9 @@ export class MainHttpProvider extends HttpProvider {
       }
 
       case "/": {
+        if (route.requestPath !== "/index.html") {
+          throw new HttpError("Not found", HttpCode.NotFound)
+        }
         const options: Options = {
           authed: !!this.authenticated(request),
           basePath: this.base(route),
diff --git a/src/node/vscode/server.ts b/src/node/vscode/server.ts
index 5193d561..de984ab5 100644
--- a/src/node/vscode/server.ts
+++ b/src/node/vscode/server.ts
@@ -11,6 +11,7 @@ import {
   VscodeOptions,
   WorkbenchOptions,
 } from "../../../lib/vscode/src/vs/server/ipc"
+import { HttpCode, HttpError } from "../../common/http"
 import { generateUuid } from "../../common/util"
 import { HttpProvider, HttpProviderOptions, HttpResponse, Route } from "../http"
 import { SettingsProvider } from "../settings"
@@ -114,6 +115,9 @@ export class VscodeHttpProvider extends HttpProvider {
     this.ensureAuthenticated(request)
     switch (route.base) {
       case "/":
+        if (route.requestPath !== "/index.html") {
+          throw new HttpError("Not found", HttpCode.NotFound)
+        }
         try {
           return await this.getRoot(request, route)
         } catch (error) {