diff --git a/package-lock.json b/package-lock.json
index 30f9b7a..de504c5 100644
--- a/package-lock.json
+++ b/package-lock.json
@@ -58,11 +58,18 @@
             "integrity": "sha1-8S4PPF13sLHN2RRpQuTpbB5N1SU="
         },
         "async": {
-            "version": "2.6.1",
-            "resolved": "https://registry.npmjs.org/async/-/async-2.6.1.tgz",
-            "integrity": "sha512-fNEiL2+AZt6AlAw/29Cr0UDe4sRAHCpEHh54WMz+Bb7QfNcFw4h3loofyJpLeQs4Yx7yuqu/2dLgM5hKOs6HlQ==",
+            "version": "2.6.4",
+            "resolved": "https://registry.npmjs.org/async/-/async-2.6.4.tgz",
+            "integrity": "sha512-mzo5dfJYwAn29PeiJ0zvwTo04zj8HDJj0Mn8TD7sno7q12prdbnasKJHhkm2c1LgrhlJ0teaea8860oxi51mGA==",
             "requires": {
-                "lodash": "^4.17.10"
+                "lodash": "^4.17.14"
+            },
+            "dependencies": {
+                "lodash": {
+                    "version": "4.17.21",
+                    "resolved": "https://registry.npmjs.org/lodash/-/lodash-4.17.21.tgz",
+                    "integrity": "sha512-v2kDEe57lecTulaDIuNTPy3Ry4gLGJ6Z1O3vE1krgXZNrsQ+LFTGHVxVjcXPs17LhbZVGedAJv8XZ1tvj5FvSg=="
+                }
             }
         },
         "asynckit": {
diff --git a/package.json b/package.json
index 3b3533d..bbe527f 100644
--- a/package.json
+++ b/package.json
@@ -18,7 +18,7 @@
         "lib": "lib"
     },
     "dependencies": {
-        "async": "^2.6.1",
+        "async": "^2.6.4",
         "base58-native": "^0.1.4",
         "bignum": "^0.13.0",
         "cli-color": "^1.4.0",