diff --git a/package.json b/package.json
index becf50b..7a6305c 100644
--- a/package.json
+++ b/package.json
@@ -30,7 +30,7 @@
     "aws-sdk-mock": "^1.7.0",
     "capture-console": "^1.0.1",
     "eslint-config-taskcluster": "^3.0.0",
-    "mocha": "4.0.1",
+    "mocha": "5.2.0",
     "mock-aws-s3": "^2.6.0",
     "nock": "^9.0.28",
     "taskcluster-lib-testing": "^10.0.0",
diff --git a/yarn.lock b/yarn.lock
index b7229d8..889bc56 100644
--- a/yarn.lock
+++ b/yarn.lock
@@ -283,9 +283,9 @@ brace-expansion@^1.1.7:
     balanced-match "^1.0.0"
     concat-map "0.0.1"
 
-browser-stdout@1.3.0:
-  version "1.3.0"
-  resolved "https://registry.yarnpkg.com/browser-stdout/-/browser-stdout-1.3.0.tgz#f351d32969d32fa5d7a5567154263d928ae3bd1f"
+browser-stdout@1.3.1:
+  version "1.3.1"
+  resolved "https://registry.yarnpkg.com/browser-stdout/-/browser-stdout-1.3.1.tgz#baa559ee14ced73452229bad7326467c61fabd60"
 
 buffer-equal-constant-time@1.0.1:
   version "1.0.1"
@@ -397,9 +397,9 @@ combined-stream@^1.0.5, combined-stream@~1.0.5:
   dependencies:
     delayed-stream "~1.0.0"
 
-commander@2.11.0:
-  version "2.11.0"
-  resolved "https://registry.yarnpkg.com/commander/-/commander-2.11.0.tgz#157152fd1e7a6c8d98a5b715cf376df928004563"
+commander@2.15.1:
+  version "2.15.1"
+  resolved "http://registry.npmjs.org/commander/-/commander-2.15.1.tgz#df46e867d0fc2aec66a34662b406a9ccafff5b0f"
 
 component-emitter@^1.2.0:
   version "1.2.1"
@@ -539,9 +539,9 @@ destroy@~1.0.4:
   version "1.0.4"
   resolved "https://registry.yarnpkg.com/destroy/-/destroy-1.0.4.tgz#978857442c44749e4206613e37946205826abd80"
 
-diff@3.3.1:
-  version "3.3.1"
-  resolved "https://registry.yarnpkg.com/diff/-/diff-3.3.1.tgz#aa8567a6eed03c531fc89d3f711cd0e5259dec75"
+diff@3.5.0:
+  version "3.5.0"
+  resolved "https://registry.yarnpkg.com/diff/-/diff-3.5.0.tgz#800c0dd1e0a8bfbc95835c202ad220fe317e5a12"
 
 doctrine@^2.0.0:
   version "2.0.0"
@@ -924,9 +924,9 @@ graceful-fs@^4.1.2:
   version "4.1.11"
   resolved "https://registry.yarnpkg.com/graceful-fs/-/graceful-fs-4.1.11.tgz#0e8bdfe4d1ddb8854d64e04ea7c00e2a026e5658"
 
-growl@1.10.3:
-  version "1.10.3"
-  resolved "https://registry.yarnpkg.com/growl/-/growl-1.10.3.tgz#1926ba90cf3edfe2adb4927f5880bc22c66c790f"
+growl@1.10.5:
+  version "1.10.5"
+  resolved "https://registry.yarnpkg.com/growl/-/growl-1.10.5.tgz#f2735dc2283674fa67478b10181059355c369e5e"
 
 har-schema@^2.0.0:
   version "2.0.0"
@@ -949,6 +949,10 @@ has-flag@^2.0.0:
   version "2.0.0"
   resolved "https://registry.yarnpkg.com/has-flag/-/has-flag-2.0.0.tgz#e8207af1cc7b30d446cc70b734b5e8be18f88d51"
 
+has-flag@^3.0.0:
+  version "3.0.0"
+  resolved "https://registry.yarnpkg.com/has-flag/-/has-flag-3.0.0.tgz#b5d454dc2199ae225699f3467e5a07f3b955bafd"
+
 hawk@2.3.0:
   version "2.3.0"
   resolved "https://registry.yarnpkg.com/hawk/-/hawk-2.3.0.tgz#20864369707c2264bb823d1c4172acd5d77ed509"
@@ -1284,18 +1288,18 @@ mimic-fn@^1.0.0:
   version "1.1.0"
   resolved "https://registry.yarnpkg.com/mimic-fn/-/mimic-fn-1.1.0.tgz#e667783d92e89dbd342818b5230b9d62a672ad18"
 
+minimatch@3.0.4, minimatch@^3.0.4:
+  version "3.0.4"
+  resolved "https://registry.yarnpkg.com/minimatch/-/minimatch-3.0.4.tgz#5166e286457f03306064be5497e8dbb0c3d32083"
+  dependencies:
+    brace-expansion "^1.1.7"
+
 minimatch@^3.0.2:
   version "3.0.3"
   resolved "https://registry.yarnpkg.com/minimatch/-/minimatch-3.0.3.tgz#2a4e4090b96b2db06a9d7df01055a62a77c9b774"
   dependencies:
     brace-expansion "^1.0.0"
 
-minimatch@^3.0.4:
-  version "3.0.4"
-  resolved "https://registry.yarnpkg.com/minimatch/-/minimatch-3.0.4.tgz#5166e286457f03306064be5497e8dbb0c3d32083"
-  dependencies:
-    brace-expansion "^1.1.7"
-
 minimist@0.0.8:
   version "0.0.8"
   resolved "https://registry.yarnpkg.com/minimist/-/minimist-0.0.8.tgz#857fcabfc3397d2625b8228262e86aa7a011b05d"
@@ -1310,20 +1314,21 @@ mkdirp@0.5.1, mkdirp@^0.5.0, mkdirp@^0.5.1:
   dependencies:
     minimist "0.0.8"
 
-mocha@4.0.1:
-  version "4.0.1"
-  resolved "https://registry.yarnpkg.com/mocha/-/mocha-4.0.1.tgz#0aee5a95cf69a4618820f5e51fa31717117daf1b"
+mocha@5.2.0:
+  version "5.2.0"
+  resolved "https://registry.yarnpkg.com/mocha/-/mocha-5.2.0.tgz#6d8ae508f59167f940f2b5b3c4a612ae50c90ae6"
   dependencies:
-    browser-stdout "1.3.0"
-    commander "2.11.0"
+    browser-stdout "1.3.1"
+    commander "2.15.1"
     debug "3.1.0"
-    diff "3.3.1"
+    diff "3.5.0"
     escape-string-regexp "1.0.5"
     glob "7.1.2"
-    growl "1.10.3"
+    growl "1.10.5"
     he "1.1.1"
+    minimatch "3.0.4"
     mkdirp "0.5.1"
-    supports-color "4.4.0"
+    supports-color "5.4.0"
 
 mock-aws-s3@^2.6.0:
   version "2.6.0"
@@ -1914,11 +1919,11 @@ superagent@~3.8.1:
     qs "^6.5.1"
     readable-stream "^2.3.5"
 
-supports-color@4.4.0:
-  version "4.4.0"
-  resolved "https://registry.yarnpkg.com/supports-color/-/supports-color-4.4.0.tgz#883f7ddabc165142b2a61427f3352ded195d1a3e"
+supports-color@5.4.0:
+  version "5.4.0"
+  resolved "https://registry.yarnpkg.com/supports-color/-/supports-color-5.4.0.tgz#1c6b337402c2137605efe19f10fec390f6faab54"
   dependencies:
-    has-flag "^2.0.0"
+    has-flag "^3.0.0"
 
 supports-color@^2.0.0:
   version "2.0.0"