diff --git a/Build/package-lock.json b/Build/package-lock.json
index aa5cb96ee..39c77ef9b 100644
--- a/Build/package-lock.json
+++ b/Build/package-lock.json
@@ -7,7 +7,7 @@
       "name": "dfg-viewer",
       "license": "GPL-3.0-or-later",
       "devDependencies": {
-        "grunt": "^1.3.0",
+        "grunt": "^1.5.3",
         "grunt-contrib-less": "^2.0.0",
         "grunt-contrib-watch": "^1.1.0",
         "grunt-terser": "^2.0.0",
@@ -529,9 +529,9 @@
       "optional": true
     },
     "node_modules/grunt": {
-      "version": "1.4.1",
-      "resolved": "https://registry.npmjs.org/grunt/-/grunt-1.4.1.tgz",
-      "integrity": "sha512-ZXIYXTsAVrA7sM+jZxjQdrBOAg7DyMUplOMhTaspMRExei+fD0BTwdWXnn0W5SXqhb/Q/nlkzXclSi3IH55PIA==",
+      "version": "1.5.3",
+      "resolved": "https://registry.npmjs.org/grunt/-/grunt-1.5.3.tgz",
+      "integrity": "sha512-mKwmo4X2d8/4c/BmcOETHek675uOqw0RuA/zy12jaspWqvTp4+ZeQF1W+OTpcbncnaBsfbQJ6l0l4j+Sn/GmaQ==",
       "dev": true,
       "dependencies": {
         "dateformat": "~3.0.3",
@@ -539,7 +539,7 @@
         "exit": "~0.1.2",
         "findup-sync": "~0.3.0",
         "glob": "~7.1.6",
-        "grunt-cli": "~1.4.2",
+        "grunt-cli": "~1.4.3",
         "grunt-known-options": "~2.0.0",
         "grunt-legacy-log": "~3.0.0",
         "grunt-legacy-util": "~2.0.1",
@@ -2075,9 +2075,9 @@
       "optional": true
     },
     "grunt": {
-      "version": "1.4.1",
-      "resolved": "https://registry.npmjs.org/grunt/-/grunt-1.4.1.tgz",
-      "integrity": "sha512-ZXIYXTsAVrA7sM+jZxjQdrBOAg7DyMUplOMhTaspMRExei+fD0BTwdWXnn0W5SXqhb/Q/nlkzXclSi3IH55PIA==",
+      "version": "1.5.3",
+      "resolved": "https://registry.npmjs.org/grunt/-/grunt-1.5.3.tgz",
+      "integrity": "sha512-mKwmo4X2d8/4c/BmcOETHek675uOqw0RuA/zy12jaspWqvTp4+ZeQF1W+OTpcbncnaBsfbQJ6l0l4j+Sn/GmaQ==",
       "dev": true,
       "requires": {
         "dateformat": "~3.0.3",
@@ -2085,7 +2085,7 @@
         "exit": "~0.1.2",
         "findup-sync": "~0.3.0",
         "glob": "~7.1.6",
-        "grunt-cli": "~1.4.2",
+        "grunt-cli": "~1.4.3",
         "grunt-known-options": "~2.0.0",
         "grunt-legacy-log": "~3.0.0",
         "grunt-legacy-util": "~2.0.1",
diff --git a/Build/package.json b/Build/package.json
index 1a6057d76..cc2ca9313 100644
--- a/Build/package.json
+++ b/Build/package.json
@@ -13,7 +13,7 @@
   "license": "GPL-3.0-or-later",
   "homepage": "https://dfgviewer.de",
   "devDependencies": {
-    "grunt": "^1.3.0",
+    "grunt": "^1.5.3",
     "grunt-contrib-less": "^2.0.0",
     "grunt-contrib-watch": "^1.1.0",
     "grunt-terser": "^2.0.0",