diff --git a/lib/createGltf.js b/lib/createGltf.js
index c314ac5..bc1d77e 100644
--- a/lib/createGltf.js
+++ b/lib/createGltf.js
@@ -274,7 +274,7 @@ function cloneMaterial(material, removeTextures) {
     }
     const clonedObject = {};
     for (const name in material) {
-        if (material.hasOwnProperty(name)) {
+        if (Object.prototype.hasOwnProperty.call(material, name)) {
             clonedObject[name] = cloneMaterial(material[name], removeTextures);
         }
     }
@@ -283,7 +283,7 @@ function cloneMaterial(material, removeTextures) {
 
 function resolveTextures(gltf, material) {
     for (const name in material) {
-        if (material.hasOwnProperty(name)) {
+        if (Object.prototype.hasOwnProperty.call(material, name)) {
             const property = material[name];
             if (property instanceof Texture) {
                 material[name] = getTexture(gltf, property);
diff --git a/package.json b/package.json
index f8d8446..fb0e7e3 100644
--- a/package.json
+++ b/package.json
@@ -26,25 +26,25 @@
     "node": ">=4.0.0"
   },
   "dependencies": {
-    "bluebird": "^3.5.3",
-    "cesium": "^1.55.0",
-    "fs-extra": "^7.0.1",
-    "jpeg-js": "^0.3.4",
-    "mime": "^2.4.0",
-    "pngjs": "^3.3.3",
-    "yargs": "^13.2.2"
+    "bluebird": "^3.5.5",
+    "cesium": "^1.58.1",
+    "fs-extra": "^8.0.1",
+    "jpeg-js": "^0.3.5",
+    "mime": "^2.4.4",
+    "pngjs": "^3.4.0",
+    "yargs": "^13.2.4"
   },
   "devDependencies": {
-    "cloc": "^2.4.0",
-    "coveralls": "^3.0.3",
-    "eslint": "^5.15.1",
-    "eslint-config-cesium": "^6.0.1",
-    "gulp": "^4.0.0",
-    "jasmine": "^3.3.1",
+    "cloc": "^2.5.0",
+    "coveralls": "^3.0.4",
+    "eslint": "^6.0.0",
+    "eslint-config-cesium": "^7.0.0",
+    "gulp": "^4.0.2",
+    "jasmine": "^3.4.0",
     "jasmine-spec-reporter": "^4.2.1",
-    "jsdoc": "^3.5.5",
-    "nyc": "^13.3.0",
-    "open": "^6.0.0",
+    "jsdoc": "^3.6.2",
+    "nyc": "^14.1.1",
+    "open": "^6.3.0",
     "requirejs": "^2.3.6"
   },
   "scripts": {