diff --git a/package-lock.json b/package-lock.json
index f4eb480..5b91cef 100644
--- a/package-lock.json
+++ b/package-lock.json
@@ -75,11 +75,11 @@
       "dev": true
     },
     "async": {
-      "version": "2.0.1",
-      "resolved": "https://registry.npmjs.org/async/-/async-2.0.1.tgz",
-      "integrity": "sha1-twnMAoCpw28J9FNr6CPIOKkEniU=",
+      "version": "2.6.4",
+      "resolved": "https://registry.npmjs.org/async/-/async-2.6.4.tgz",
+      "integrity": "sha512-mzo5dfJYwAn29PeiJ0zvwTo04zj8HDJj0Mn8TD7sno7q12prdbnasKJHhkm2c1LgrhlJ0teaea8860oxi51mGA==",
       "requires": {
-        "lodash": "^4.8.0"
+        "lodash": "^4.17.14"
       }
     },
     "async-each": {
diff --git a/package.json b/package.json
index 82a2667..ba7a8d0 100644
--- a/package.json
+++ b/package.json
@@ -31,7 +31,7 @@
   },
   "dependencies": {
     "argparse": "1.0.7",
-    "async": "2.0.1",
+    "async": "2.6.4",
     "bn.js": "^4.11.6",
     "bunyan": "1.8.12",
     "md5": "2.1.0",