diff --git a/package-lock.json b/package-lock.json
index 39f81b6..c9c95c8 100644
--- a/package-lock.json
+++ b/package-lock.json
@@ -172,7 +172,7 @@
                 },
                 "util": {
                     "version": "0.10.3",
-                    "resolved": "http://registry.npmjs.org/util/-/util-0.10.3.tgz",
+                    "resolved": "https://registry.npmjs.org/util/-/util-0.10.3.tgz",
                     "integrity": "sha1-evsa/lCAUkZInj23/g7TeTNqwPk=",
                     "dev": true,
                     "requires": {
@@ -993,18 +993,32 @@
             "dev": true
         },
         "elliptic": {
-            "version": "6.4.1",
-            "resolved": "https://registry.npmjs.org/elliptic/-/elliptic-6.4.1.tgz",
-            "integrity": "sha512-BsXLz5sqX8OHcsh7CqBMztyXARmGQ3LWPtGjJi6DiJHq5C/qvi9P3OqgswKSDftbu8+IoI/QDTAm2fFnQ9SZSQ==",
+            "version": "6.5.4",
+            "resolved": "https://registry.npmjs.org/elliptic/-/elliptic-6.5.4.tgz",
+            "integrity": "sha512-iLhC6ULemrljPZb+QutR5TQGB+pdW6KGD5RSegS+8sorOZT+rdQFbsQFJgvN3eRqNALqJer4oQ16YvJHlU8hzQ==",
             "dev": true,
             "requires": {
-                "bn.js": "^4.4.0",
-                "brorand": "^1.0.1",
+                "bn.js": "^4.11.9",
+                "brorand": "^1.1.0",
                 "hash.js": "^1.0.0",
-                "hmac-drbg": "^1.0.0",
-                "inherits": "^2.0.1",
-                "minimalistic-assert": "^1.0.0",
-                "minimalistic-crypto-utils": "^1.0.0"
+                "hmac-drbg": "^1.0.1",
+                "inherits": "^2.0.4",
+                "minimalistic-assert": "^1.0.1",
+                "minimalistic-crypto-utils": "^1.0.1"
+            },
+            "dependencies": {
+                "bn.js": {
+                    "version": "4.12.0",
+                    "resolved": "https://registry.npmjs.org/bn.js/-/bn.js-4.12.0.tgz",
+                    "integrity": "sha512-c98Bf3tPniI+scsdk237ku1Dc3ujXQTSgyiPUDEOe7tRkhrqridvh8klBv0HCEso1OLOYcHuCv/cS6DNxKH+ZA==",
+                    "dev": true
+                },
+                "inherits": {
+                    "version": "2.0.4",
+                    "resolved": "https://registry.npmjs.org/inherits/-/inherits-2.0.4.tgz",
+                    "integrity": "sha512-k/vGaX4/Yla3WzyMCvTQOXYeIHvqOKtnqBduzTHpzpQZzAskKMhZ2K+EnBiSM9zGSoIFeMpXKxa4dYeZIQqewQ==",
+                    "dev": true
+                }
             }
         },
         "error-ex": {
@@ -1829,7 +1843,7 @@
             "dependencies": {
                 "semver": {
                     "version": "5.3.0",
-                    "resolved": "http://registry.npmjs.org/semver/-/semver-5.3.0.tgz",
+                    "resolved": "https://registry.npmjs.org/semver/-/semver-5.3.0.tgz",
                     "integrity": "sha1-myzl094C0XxgEq0yaqa00M9U+U8=",
                     "dev": true
                 }
@@ -2558,7 +2572,7 @@
             "dependencies": {
                 "string_decoder": {
                     "version": "1.1.1",
-                    "resolved": "http://registry.npmjs.org/string_decoder/-/string_decoder-1.1.1.tgz",
+                    "resolved": "https://registry.npmjs.org/string_decoder/-/string_decoder-1.1.1.tgz",
                     "integrity": "sha512-n/ShnvDi6FHbbVfviro+WojiFzv+s8MPMHBczVePfUpDJLwoLT0ht1l4YwBCbi8pJAveEEdnkHyPyTP/mzRfwg==",
                     "dev": true,
                     "requires": {
@@ -2732,7 +2746,7 @@
             "dependencies": {
                 "source-map": {
                     "version": "0.4.4",
-                    "resolved": "http://registry.npmjs.org/source-map/-/source-map-0.4.4.tgz",
+                    "resolved": "https://registry.npmjs.org/source-map/-/source-map-0.4.4.tgz",
                     "integrity": "sha1-66T12pwNyZneaAMti092FzZSA2s=",
                     "dev": true,
                     "requires": {