diff --git a/package-lock.json b/package-lock.json
index b3ce334..ce02bae 100644
--- a/package-lock.json
+++ b/package-lock.json
@@ -1,15 +1,25 @@
 {
   "name": "solidity-course",
   "version": "1.0.0",
-  "lockfileVersion": 1,
+  "lockfileVersion": 3,
   "requires": true,
-  "dependencies": {
-    "bn.js": {
-      "version": "5.0.0",
-      "resolved": "https://registry.npmjs.org/bn.js/-/bn.js-5.0.0.tgz",
-      "integrity": "sha512-bVwDX8AF+72fIUNuARelKAlQUNtPOfG2fRxorbVvFk4zpHbqLrPdOGfVg5vrKwVzLLePqPBiATaOZNELQzmS0A=="
+  "packages": {
+    "": {
+      "version": "1.0.0",
+      "license": "MIT",
+      "dependencies": {
+        "bn.js": "^5.2.3",
+        "openzeppelin-solidity": "^2.4.0"
+      },
+      "devDependencies": {}
     },
-    "openzeppelin-solidity": {
+    "node_modules/bn.js": {
+      "version": "5.2.3",
+      "resolved": "https://registry.npmjs.org/bn.js/-/bn.js-5.2.3.tgz",
+      "integrity": "sha512-EAcmnPkxpntVL+DS7bO1zhcZNvCkxqtkd0ZY53h06GNQ3DEkkGZ/gKgmDv6DdZQGj9BgfSPKtJJ7Dp1GPP8f7w==",
+      "license": "MIT"
+    },
+    "node_modules/openzeppelin-solidity": {
       "version": "2.4.0",
       "resolved": "https://registry.npm.taobao.org/openzeppelin-solidity/download/openzeppelin-solidity-2.4.0.tgz",
       "integrity": "sha1-Xwp7MFccRUk0SRZuV7lHIDQVNJ0="
diff --git a/package.json b/package.json
index ce140f2..9cf66ea 100644
--- a/package.json
+++ b/package.json
@@ -7,7 +7,7 @@
     "test": "test"
   },
   "dependencies": {
-    "bn.js": "^5.0.0",
+    "bn.js": "^5.2.3",
     "openzeppelin-solidity": "^2.4.0"
   },
   "devDependencies": {},