diff --git a/package-lock.json b/package-lock.json
index 513eac9..329079d 100644
--- a/package-lock.json
+++ b/package-lock.json
@@ -42,9 +42,12 @@
       "dev": true
     },
     "async": {
-      "version": "1.5.2",
-      "resolved": "https://registry.npmjs.org/async/-/async-1.5.2.tgz",
-      "integrity": "sha1-7GphrlZIDAw8skHJVhjiCJL5Zyo="
+      "version": "2.6.4",
+      "resolved": "https://registry.npmjs.org/async/-/async-2.6.4.tgz",
+      "integrity": "sha512-mzo5dfJYwAn29PeiJ0zvwTo04zj8HDJj0Mn8TD7sno7q12prdbnasKJHhkm2c1LgrhlJ0teaea8860oxi51mGA==",
+      "requires": {
+        "lodash": "^4.17.14"
+      }
     },
     "balanced-match": {
       "version": "1.0.0",
@@ -500,6 +503,14 @@
         "async": "^1.4.0",
         "combined-stream": "^1.0.5",
         "mime-types": "^2.1.3"
+      },
+      "dependencies": {
+        "async": {
+          "version": "1.5.2",
+          "resolved": "https://registry.npmjs.org/async/-/async-1.5.2.tgz",
+          "integrity": "sha1-7GphrlZIDAw8skHJVhjiCJL5Zyo=",
+          "dev": true
+        }
       }
     },
     "formidable": {
@@ -706,6 +717,12 @@
         "wordwrap": "^1.0.0"
       },
       "dependencies": {
+        "async": {
+          "version": "1.5.2",
+          "resolved": "https://registry.npmjs.org/async/-/async-1.5.2.tgz",
+          "integrity": "sha1-7GphrlZIDAw8skHJVhjiCJL5Zyo=",
+          "dev": true
+        },
         "esprima": {
           "version": "2.7.3",
           "resolved": "https://registry.npmjs.org/esprima/-/esprima-2.7.3.tgz",
@@ -752,8 +769,7 @@
     "lodash": {
       "version": "4.17.15",
       "resolved": "https://registry.npmjs.org/lodash/-/lodash-4.17.15.tgz",
-      "integrity": "sha512-8xOcRHvCjnocdS5cpwXQXVzmmh5e5+saE2QGoeQmbKmRS6J3VQppPOIt0MnmE+4xlZoumy0GPG0D0MVIQbNA1A==",
-      "dev": true
+      "integrity": "sha512-8xOcRHvCjnocdS5cpwXQXVzmmh5e5+saE2QGoeQmbKmRS6J3VQppPOIt0MnmE+4xlZoumy0GPG0D0MVIQbNA1A=="
     },
     "media-typer": {
       "version": "0.3.0",
diff --git a/package.json b/package.json
index 098abd2..69af5a4 100644
--- a/package.json
+++ b/package.json
@@ -31,7 +31,7 @@
     "node": "<=4.x"
   },
   "dependencies": {
-    "async": "^1.5.0",
+    "async": "^2.6.4",
     "caller": "^1.0.1",
     "core-util-is": "^1.0.1",
     "debuglog": "^1.0.1",