diff --git a/yarn.lock b/yarn.lock
index 88fd2b2..d6ed941 100644
--- a/yarn.lock
+++ b/yarn.lock
@@ -88,6 +88,10 @@ assertion-error@^1.0.1:
   version "1.0.2"
   resolved "https://registry.yarnpkg.com/assertion-error/-/assertion-error-1.0.2.tgz#13ca515d86206da0bac66e834dd397d87581094c"
 
+async-limiter@~1.0.0:
+  version "1.0.1"
+  resolved "https://registry.yarnpkg.com/async-limiter/-/async-limiter-1.0.1.tgz#dd379e94f0db8310b08291f9d64c3209766617fd"
+
 async@1.x, async@^1.4.0:
   version "1.5.2"
   resolved "https://registry.yarnpkg.com/async/-/async-1.5.2.tgz#ec6a61ae56480c0c3cb241c95618e20892f9672a"
@@ -1368,12 +1372,8 @@ rimraf@^2.6.1:
     glob "^7.0.5"
 
 safe-buffer@^5.0.1, safe-buffer@^5.1.0, safe-buffer@~5.1.0, safe-buffer@~5.1.1:
-  version "5.1.1"
-  resolved "https://registry.yarnpkg.com/safe-buffer/-/safe-buffer-5.1.1.tgz#893312af69b2123def71f57889001671eeb2c853"
-
-safe-buffer@~5.0.1:
-  version "5.0.1"
-  resolved "https://registry.yarnpkg.com/safe-buffer/-/safe-buffer-5.0.1.tgz#d263ca54696cd8a306b5ca6551e92de57918fbe7"
+  version "5.1.2"
+  resolved "https://registry.yarnpkg.com/safe-buffer/-/safe-buffer-5.1.2.tgz#991ec69d296e0313747d59bdfd2b745c35f8828d"
 
 "semver@2 || 3 || 4 || 5", semver@^5.3.0:
   version "5.3.0"
@@ -1585,8 +1585,8 @@ uglify-to-browserify@~1.0.0:
   resolved "https://registry.yarnpkg.com/uglify-to-browserify/-/uglify-to-browserify-1.0.2.tgz#6e0924d6bda6b5afe349e39a6d632850a0f882b7"
 
 ultron@~1.1.0:
-  version "1.1.0"
-  resolved "https://registry.yarnpkg.com/ultron/-/ultron-1.1.0.tgz#b07a2e6a541a815fc6a34ccd4533baec307ca864"
+  version "1.1.1"
+  resolved "https://registry.yarnpkg.com/ultron/-/ultron-1.1.1.tgz#9fe1536a10a664a65266a1e3ccf85fd36302bc9c"
 
 unc-path-regex@^0.1.0:
   version "0.1.2"
@@ -1656,10 +1656,11 @@ wrappy@1:
   resolved "https://registry.yarnpkg.com/wrappy/-/wrappy-1.0.2.tgz#b5243d8f3ec1aa35f1364605bc0d1036e30ab69f"
 
 ws@^3.0.0:
-  version "3.0.0"
-  resolved "https://registry.yarnpkg.com/ws/-/ws-3.0.0.tgz#98ddb00056c8390cb751e7788788497f99103b6c"
+  version "3.3.3"
+  resolved "https://registry.yarnpkg.com/ws/-/ws-3.3.3.tgz#f1cf84fe2d5e901ebce94efaece785f187a228f2"
   dependencies:
-    safe-buffer "~5.0.1"
+    async-limiter "~1.0.0"
+    safe-buffer "~5.1.0"
     ultron "~1.1.0"
 
 xtend@^4.0.0, xtend@^4.0.1, xtend@~4.0.0, xtend@~4.0.1: