diff --git a/yarn.lock b/yarn.lock
index 4edaf7e7..7d88529f 100644
--- a/yarn.lock
+++ b/yarn.lock
@@ -558,9 +558,9 @@
     "@babel/types" "^7.3.0"
 
 "@types/chai@*", "@types/chai@^4.2.6":
-  version "4.2.11"
-  resolved "https://registry.yarnpkg.com/@types/chai/-/chai-4.2.11.tgz#d3614d6c5f500142358e6ed24e1bf16657536c50"
-  integrity sha512-t7uW6eFafjO+qJ3BIV2gGUyZs27egcNRkUdalkud+Qa3+kg//f129iuOFivHDXQ+vnU3fDXuwgv0cqMCbcE8sw==
+  version "4.2.21"
+  resolved "https://registry.yarnpkg.com/@types/chai/-/chai-4.2.21.tgz#9f35a5643129df132cf3b5c1ec64046ea1af0650"
+  integrity sha512-yd+9qKmJxm496BOV9CMNaey8TWsikaZOwMRwPHQIjcOJM9oV+fi9ZMNw3JsVnbEEbo2gRTDnGEBv8pjyn67hNg==
 
 "@types/color-name@^1.1.1":
   version "1.1.1"