diff --git a/package.json b/package.json
index dd66edf..ab83c5c 100644
--- a/package.json
+++ b/package.json
@@ -24,7 +24,7 @@
     "eslint": "^7.0.0",
     "eslint-config-taskcluster": "^4.0.0",
     "lodash": "^4.17.15",
-    "mocha": "8.3.2"
+    "mocha": "8.4.0"
   },
   "dependencies": {
     "fast-json-stable-stringify": "^2.1.0"
diff --git a/yarn.lock b/yarn.lock
index 70528af..a37089b 100644
--- a/yarn.lock
+++ b/yarn.lock
@@ -719,10 +719,10 @@ minimatch@3.0.4, minimatch@^3.0.4:
   dependencies:
     brace-expansion "^1.1.7"
 
-mocha@8.3.2:
-  version "8.3.2"
-  resolved "https://registry.yarnpkg.com/mocha/-/mocha-8.3.2.tgz#53406f195fa86fbdebe71f8b1c6fb23221d69fcc"
-  integrity sha512-UdmISwr/5w+uXLPKspgoV7/RXZwKRTiTjJ2/AC5ZiEztIoOYdfKb19+9jNmEInzx5pBsCyJQzarAxqIGBNYJhg==
+mocha@8.4.0:
+  version "8.4.0"
+  resolved "https://registry.yarnpkg.com/mocha/-/mocha-8.4.0.tgz#677be88bf15980a3cae03a73e10a0fc3997f0cff"
+  integrity sha512-hJaO0mwDXmZS4ghXsvPVriOhsxQ7ofcpQdm8dE+jISUOKopitvnXFQmpRR7jd2K6VBG6E26gU3IAbXXGIbu4sQ==
   dependencies:
     "@ungap/promise-all-settled" "1.1.2"
     ansi-colors "4.1.1"