diff --git a/package-lock.json b/package-lock.json
index 1134bba..4c8ff55 100644
--- a/package-lock.json
+++ b/package-lock.json
@@ -2143,13 +2143,13 @@
       }
     },
     "ethereumjs-util": {
-      "version": "6.0.0",
-      "resolved": "https://registry.npmjs.org/ethereumjs-util/-/ethereumjs-util-6.0.0.tgz",
-      "integrity": "sha512-E3yKUyl0Fs95nvTFQZe/ZSNcofhDzUsDlA5y2uoRmf1+Ec7gpGhNCsgKkZBRh7Br5op8mJcYF/jFbmjj909+nQ==",
+      "version": "6.1.0",
+      "resolved": "https://registry.npmjs.org/ethereumjs-util/-/ethereumjs-util-6.1.0.tgz",
+      "integrity": "sha512-URESKMFbDeJxnAxPppnk2fN6Y3BIatn9fwn76Lm8bQlt+s52TpG8dN9M66MLPuRAiAOIqL3dfwqWJf0sd0fL0Q==",
       "requires": {
         "bn.js": "^4.11.0",
         "create-hash": "^1.1.2",
-        "ethjs-util": "^0.1.6",
+        "ethjs-util": "0.1.6",
         "keccak": "^1.0.2",
         "rlp": "^2.0.0",
         "safe-buffer": "^5.1.1",
@@ -2754,11 +2754,13 @@
         },
         "balanced-match": {
           "version": "1.0.0",
-          "bundled": true
+          "bundled": true,
+          "optional": true
         },
         "brace-expansion": {
           "version": "1.1.11",
           "bundled": true,
+          "optional": true,
           "requires": {
             "balanced-match": "^1.0.0",
             "concat-map": "0.0.1"
@@ -2771,15 +2773,18 @@
         },
         "code-point-at": {
           "version": "1.1.0",
-          "bundled": true
+          "bundled": true,
+          "optional": true
         },
         "concat-map": {
           "version": "0.0.1",
-          "bundled": true
+          "bundled": true,
+          "optional": true
         },
         "console-control-strings": {
           "version": "1.1.0",
-          "bundled": true
+          "bundled": true,
+          "optional": true
         },
         "core-util-is": {
           "version": "1.0.2",
@@ -2882,7 +2887,8 @@
         },
         "inherits": {
           "version": "2.0.3",
-          "bundled": true
+          "bundled": true,
+          "optional": true
         },
         "ini": {
           "version": "1.3.5",
@@ -2892,6 +2898,7 @@
         "is-fullwidth-code-point": {
           "version": "1.0.0",
           "bundled": true,
+          "optional": true,
           "requires": {
             "number-is-nan": "^1.0.0"
           }
@@ -2904,17 +2911,20 @@
         "minimatch": {
           "version": "3.0.4",
           "bundled": true,
+          "optional": true,
           "requires": {
             "brace-expansion": "^1.1.7"
           }
         },
         "minimist": {
           "version": "0.0.8",
-          "bundled": true
+          "bundled": true,
+          "optional": true
         },
         "minipass": {
           "version": "2.2.4",
           "bundled": true,
+          "optional": true,
           "requires": {
             "safe-buffer": "^5.1.1",
             "yallist": "^3.0.0"
@@ -2931,6 +2941,7 @@
         "mkdirp": {
           "version": "0.5.1",
           "bundled": true,
+          "optional": true,
           "requires": {
             "minimist": "0.0.8"
           }
@@ -3003,7 +3014,8 @@
         },
         "number-is-nan": {
           "version": "1.0.1",
-          "bundled": true
+          "bundled": true,
+          "optional": true
         },
         "object-assign": {
           "version": "4.1.1",
@@ -3013,6 +3025,7 @@
         "once": {
           "version": "1.4.0",
           "bundled": true,
+          "optional": true,
           "requires": {
             "wrappy": "1"
           }
@@ -3118,6 +3131,7 @@
         "string-width": {
           "version": "1.0.2",
           "bundled": true,
+          "optional": true,
           "requires": {
             "code-point-at": "^1.0.0",
             "is-fullwidth-code-point": "^1.0.0",
diff --git a/package.json b/package.json
index 3800588..55a6a2a 100644
--- a/package.json
+++ b/package.json
@@ -33,6 +33,6 @@
   "dependencies": {
     "@ethereum-alarm-clock/contracts": "1.0.0-rc.2",
     "bignumber.js": "5.0.0",
-    "ethereumjs-util": "6.0.0"
+    "ethereumjs-util": "6.1.0"
   }
 }