diff --git a/app.js b/app.js
index 61b9422fc..a3def3edf 100644
--- a/app.js
+++ b/app.js
@@ -9,7 +9,6 @@ const session = require('express-session');
 const FileStore = require('session-file-store')(session);
 const os = require('os');
 const sessionSecret = require('./services/session_secret');
-const utils = require('./services/utils');
 
 require('./services/ping_job');
 
@@ -30,12 +29,12 @@ app.use(bodyParser.json({limit: '50mb'}));
 app.use(bodyParser.urlencoded({extended: false}));
 app.use(cookieParser());
 app.use(express.static(path.join(__dirname, 'public')));
-app.use(session({
+const sessionParser = session({
     secret: sessionSecret,
     resave: false, // true forces the session to be saved back to the session store, even if the session was never modified during the request.
     saveUninitialized: false, // true forces a session that is "uninitialized" to be saved to the store. A session is uninitialized when it is new but not modified.
     cookie: {
-    //    path: "/",
+        //    path: "/",
         httpOnly: true,
         maxAge:  1800000
     },
@@ -43,7 +42,8 @@ app.use(session({
         ttl: 30 * 24 * 3600,
         path: os.tmpdir() + '/trilium-sessions'
     })
-}));
+});
+app.use(sessionParser);
 
 app.use(favicon(__dirname + '/public/images/app-icons/win/icon.ico'));
 
@@ -72,4 +72,7 @@ require('./services/sync');
 // triggers backup timer
 require('./services/backup');
 
-module.exports = app;
\ No newline at end of file
+module.exports = {
+    app,
+    sessionParser
+};
\ No newline at end of file
diff --git a/bin/www b/bin/www
index 7c6a49396..ca32874bb 100755
--- a/bin/www
+++ b/bin/www
@@ -8,7 +8,7 @@ process.on('unhandledRejection', error => {
     require('../services/log').info(error);
 });
 
-const app = require('../app');
+const { app, sessionParser } = require('../app');
 const debug = require('debug')('node:server');
 const fs = require('fs');
 const http = require('http');
@@ -53,7 +53,7 @@ httpServer.listen(port);
 httpServer.on('error', onError);
 httpServer.on('listening', onListening);
 
-messaging.init(httpServer);
+messaging.init(httpServer, sessionParser);
 
 if (utils.isElectron()) {
     const electronRouting = require('../routes/electron');
diff --git a/services/messaging.js b/services/messaging.js
index 70fe674e4..9621d6d9f 100644
--- a/services/messaging.js
+++ b/services/messaging.js
@@ -1,9 +1,25 @@
 const WebSocket = require('ws');
+const utils = require('./utils');
+const log = require('./log');
 
 let webSocketServer;
 
-function init(httpServer) {
-    webSocketServer = new WebSocket.Server({server: httpServer});
+function init(httpServer, sessionParser) {
+    webSocketServer = new WebSocket.Server({
+        verifyClient: (info, done) => {
+            sessionParser(info.req, {}, () => {
+                const allowed = utils.isElectron() || info.req.session.loggedIn;
+
+                if (!allowed) {
+                    log.error("WebSocket connection not allowed because session is neither electron nor logged in.");
+                }
+
+                done(allowed)
+            });
+        },
+        server: httpServer
+    });
+
     webSocketServer.on('connection', function connection(ws, req) {
         console.log("websocket client connected");
     });