diff --git a/package-lock.json b/package-lock.json
index 40a1a26..809897e 100644
--- a/package-lock.json
+++ b/package-lock.json
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@@ -7569,6 +7545,23 @@
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@@ -8333,39 +8326,39 @@
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-        "nise": "^1.4.10",
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diff --git a/package.json b/package.json
index 41f3f99..9235318 100644
--- a/package.json
+++ b/package.json
@@ -33,7 +33,7 @@
     "mocha": "^4.1.0",
     "nyc": "^13.3.0",
     "prettier": "^1.10.2",
-    "sinon": "^7.2.3"
+    "sinon": "^8.1.1"
   },
   "dependencies": {
     "@govtechsg/open-certificate": "2.0.6",