diff --git a/react/countdown/yarn.lock b/react/countdown/yarn.lock
index e547b33..ede1629 100644
--- a/react/countdown/yarn.lock
+++ b/react/countdown/yarn.lock
@@ -1073,9 +1073,9 @@ acorn-dynamic-import@^3.0.0:
     acorn "^5.0.0"
 
 acorn@^5.0.0:
-  version "5.6.2"
-  resolved "https://registry.yarnpkg.com/acorn/-/acorn-5.6.2.tgz#b1da1d7be2ac1b4a327fb9eab851702c5045b4e7"
-  integrity sha512-zUzo1E5dI2Ey8+82egfnttyMlMZ2y0D8xOCO3PNPPlYXpl8NZvF6Qk9L9BEtJs+43FqEmfBViDqc5d1ckRDguw==
+  version "5.7.4"
+  resolved "https://registry.yarnpkg.com/acorn/-/acorn-5.7.4.tgz#3e8d8a9947d0599a1796d10225d7432f4a4acf5e"
+  integrity sha512-1D++VG7BhrtvQpNbBzovKNc1FLGGEE/oGe7b9xJm/RFHMBeUaUGpluV9RLjZa47YFdPcDAenEYuq9pQPcMdLJg==
 
 ajv-keywords@^3.1.0:
   version "3.2.0"
@@ -2962,7 +2962,7 @@ express-mung@^0.5.1:
 
 express@^4.16.3:
   version "4.16.3"
-  resolved "http://registry.npmjs.org/express/-/express-4.16.3.tgz#6af8a502350db3246ecc4becf6b5a34d22f7ed53"
+  resolved "https://registry.npmjs.org/express/-/express-4.16.3.tgz#6af8a502350db3246ecc4becf6b5a34d22f7ed53"
   integrity sha1-avilAjUNsyRuzEvs9rWjTSL37VM=
   dependencies:
     accepts "~1.3.5"
@@ -3153,7 +3153,7 @@ fill-range@^4.0.0:
 
 finalhandler@1.1.1:
   version "1.1.1"
-  resolved "http://registry.npmjs.org/finalhandler/-/finalhandler-1.1.1.tgz#eebf4ed840079c83f4249038c9d703008301b105"
+  resolved "https://registry.npmjs.org/finalhandler/-/finalhandler-1.1.1.tgz#eebf4ed840079c83f4249038c9d703008301b105"
   integrity sha512-Y1GUDo39ez4aHAw7MysnUD5JzYX+WaIj8I57kO3aEPT1fFRL4sr7mjei97FgnwhAyyzRYmQZaTHb2+9uZ1dPtg==
   dependencies:
     debug "2.6.9"
@@ -3684,7 +3684,7 @@ http-errors@^1.2.8, http-errors@^1.6.1, http-errors@~1.6.1, http-errors@~1.6.2:
 
 http-proxy-middleware@^0.18.0:
   version "0.18.0"
-  resolved "http://registry.npmjs.org/http-proxy-middleware/-/http-proxy-middleware-0.18.0.tgz#0987e6bb5a5606e5a69168d8f967a87f15dd8aab"
+  resolved "https://registry.npmjs.org/http-proxy-middleware/-/http-proxy-middleware-0.18.0.tgz#0987e6bb5a5606e5a69168d8f967a87f15dd8aab"
   integrity sha512-Fs25KVMPAIIcgjMZkVHJoKg9VcXcC1C8yb9JUgeDvVXY0S/zgVIhMb+qVswDIgtJe2DfckMSY2d6TuTEutlk6Q==
   dependencies:
     http-proxy "^1.16.2"
@@ -4470,7 +4470,7 @@ leb@^0.3.0:
 
 load-json-file@^1.0.0:
   version "1.1.0"
-  resolved "http://registry.npmjs.org/load-json-file/-/load-json-file-1.1.0.tgz#956905708d58b4bab4c2261b04f59f31c99374c0"
+  resolved "https://registry.npmjs.org/load-json-file/-/load-json-file-1.1.0.tgz#956905708d58b4bab4c2261b04f59f31c99374c0"
   integrity sha1-lWkFcI1YtLq0wiYbBPWfMcmTdMA=
   dependencies:
     graceful-fs "^4.1.2"
@@ -5403,7 +5403,7 @@ p-finally@^1.0.0:
 
 p-is-promise@^1.1.0:
   version "1.1.0"
-  resolved "http://registry.npmjs.org/p-is-promise/-/p-is-promise-1.1.0.tgz#9c9456989e9f6588017b0434d56097675c3da05e"
+  resolved "https://registry.npmjs.org/p-is-promise/-/p-is-promise-1.1.0.tgz#9c9456989e9f6588017b0434d56097675c3da05e"
   integrity sha1-nJRWmJ6fZYgBewQ01WCXZ1w9oF4=
 
 p-limit@^1.1.0: