diff --git a/io-package.json b/io-package.json
index 91a464d..2da3c6d 100644
--- a/io-package.json
+++ b/io-package.json
@@ -1,8 +1,20 @@
 {
     "common": {
         "name": "discovery",
-        "version": "2.3.3",
+        "version": "2.3.4",
         "news": {
+            "2.3.4": {
+                "en": "potential crash case fixed",
+                "de": "Möglicher Crash-Fall behoben",
+                "ru": "случай возможного сбоя исправлен",
+                "pt": "possível caso de falha corrigido",
+                "nl": "mogelijke crash case opgelost",
+                "fr": "cas de crash potentiel corrigé",
+                "it": "potenziale caso di crash risolto",
+                "es": "caso de bloqueo potencial solucionado",
+                "pl": "naprawiono potencjalną awarię",
+                "zh-cn": "修复潜在的崩溃案例"
+            },
             "2.3.3": {
                 "en": "potential crash case fixed",
                 "de": "Möglicher Crash-Fall behoben",
diff --git a/lib/tools.js b/lib/tools.js
index c967f30..c899039 100644
--- a/lib/tools.js
+++ b/lib/tools.js
@@ -523,6 +523,11 @@ function httpGet(link, timeout, callback) {
     }
     timeout = parseInt(timeout, 10) || 500;
 
+    if (!link) {
+        callback && callback('error: no link provided', null, link);
+        callback = null;
+    }
+
     try {
         const req = HTTP.get(link, res => {
             const statusCode = res.statusCode;
diff --git a/package-lock.json b/package-lock.json
index 244f133..563bbe7 100644
--- a/package-lock.json
+++ b/package-lock.json
@@ -1,6 +1,6 @@
 {
   "name": "iobroker.discovery",
-  "version": "2.3.3",
+  "version": "2.3.4",
   "lockfileVersion": 1,
   "requires": true,
   "dependencies": {
diff --git a/package.json b/package.json
index 44d40f5..a2d5a8e 100644
--- a/package.json
+++ b/package.json
@@ -1,7 +1,7 @@
 {
     "name": "iobroker.discovery",
     "description": "This adapter tries to detect devices in local network.",
-    "version": "2.3.3",
+    "version": "2.3.4",
     "author": "bluefox <dogafox@gmail.com>",
     "contributors": [
         "bluefox <dogafox@gmail.com>",