diff --git a/package.json b/package.json
index 9a3e39cb..403a759c 100644
--- a/package.json
+++ b/package.json
@@ -95,7 +95,7 @@
     "@testing-library/react": "^11.0.2",
     "@types/common-tags": "^1.8.0",
     "@types/jest": "^26.0.13",
-    "@types/js-base64": "^2.3.1",
+    "@types/js-base64": "^3.0.0",
     "@types/jwt-decode": "^2.2.1",
     "@types/lodash": "^4.14.149",
     "@types/uuid": "^3.4.6",
diff --git a/packages/netlify-cms-backend-bitbucket/package.json b/packages/netlify-cms-backend-bitbucket/package.json
index 5c84d874..43dd3f24 100644
--- a/packages/netlify-cms-backend-bitbucket/package.json
+++ b/packages/netlify-cms-backend-bitbucket/package.json
@@ -21,7 +21,7 @@
   },
   "dependencies": {
     "common-tags": "^1.8.0",
-    "js-base64": "^2.5.1",
+    "js-base64": "^3.0.0",
     "semaphore": "^1.1.0",
     "what-the-diff": "^0.6.0"
   },
diff --git a/packages/netlify-cms-backend-github/package.json b/packages/netlify-cms-backend-github/package.json
index 41aa84fa..75eed294 100644
--- a/packages/netlify-cms-backend-github/package.json
+++ b/packages/netlify-cms-backend-github/package.json
@@ -28,7 +28,7 @@
     "common-tags": "^1.8.0",
     "graphql": "^15.0.0",
     "graphql-tag": "^2.10.1",
-    "js-base64": "^2.5.1",
+    "js-base64": "^3.0.0",
     "semaphore": "^1.1.0"
   },
   "peerDependencies": {
diff --git a/packages/netlify-cms-backend-gitlab/package.json b/packages/netlify-cms-backend-gitlab/package.json
index 62b8b148..3d07dfc7 100644
--- a/packages/netlify-cms-backend-gitlab/package.json
+++ b/packages/netlify-cms-backend-gitlab/package.json
@@ -20,7 +20,7 @@
     "build:esm": "cross-env NODE_ENV=esm babel src --out-dir dist/esm --ignore \"**/__tests__\" --root-mode upward --extensions \".js,.jsx,.ts,.tsx\""
   },
   "dependencies": {
-    "js-base64": "^2.5.1",
+    "js-base64": "^3.0.0",
     "semaphore": "^1.1.0"
   },
   "peerDependencies": {
diff --git a/packages/netlify-cms-core/package.json b/packages/netlify-cms-core/package.json
index 3367c92b..4ec31029 100644
--- a/packages/netlify-cms-core/package.json
+++ b/packages/netlify-cms-core/package.json
@@ -37,7 +37,7 @@
     "gray-matter": "^4.0.2",
     "history": "^4.7.2",
     "immer": "^3.1.3",
-    "js-base64": "^2.5.1",
+    "js-base64": "^3.0.0",
     "jwt-decode": "^2.1.0",
     "node-polyglot": "^2.3.0",
     "prop-types": "^15.7.2",
diff --git a/yarn.lock b/yarn.lock
index 68ebd797..7110abb8 100644
--- a/yarn.lock
+++ b/yarn.lock
@@ -3481,10 +3481,10 @@
     jest-diff "^25.2.1"
     pretty-format "^25.2.1"
 
-"@types/js-base64@^2.3.1":
-  version "2.3.2"
-  resolved "https://registry.yarnpkg.com/@types/js-base64/-/js-base64-2.3.2.tgz#266be882b28b52649b1d34db9515e54c8ef783f2"
-  integrity sha512-iGjZEnheu9n53fhlU+QLovdKHsdwPJ79iammNM0opTEp18zcJ/nNAIthuMilJoDPNUQHoqRAJdDNI5rxHY4nkA==
+"@types/js-base64@^3.0.0":
+  version "3.0.0"
+  resolved "https://registry.yarnpkg.com/@types/js-base64/-/js-base64-3.0.0.tgz#b7b4c130facefefd5c57ba82664c41e2995f91be"
+  integrity sha512-BnEyOcDE4H6bkg8m84xhdbkYoAoCg8sYERmAvE4Ff50U8jTfbmOinRdJpauBn1P9XsCCQgCLuSiyz3PM4WHYOA==
 
 "@types/json-schema@^7.0.3":
   version "7.0.5"
@@ -11277,10 +11277,10 @@ jquery@^3.4.0, jquery@^3.4.1:
   resolved "https://registry.yarnpkg.com/jquery/-/jquery-3.5.1.tgz#d7b4d08e1bfdb86ad2f1a3d039ea17304717abb5"
   integrity sha512-XwIBPqcMn57FxfT+Go5pzySnm4KWkT1Tv7gjrpT1srtf8Weynl6R273VJ5GjkRb51IzMp5nbaPjJXMWeju2MKg==
 
-js-base64@^2.5.1:
-  version "2.6.4"
-  resolved "https://registry.yarnpkg.com/js-base64/-/js-base64-2.6.4.tgz#f4e686c5de1ea1f867dbcad3d46d969428df98c4"
-  integrity sha512-pZe//GGmwJndub7ZghVHz7vjb2LgC1m8B07Au3eYqeqv9emhESByMXxaEgkUkEqJe87oBbSniGYoQNIBklc7IQ==
+js-base64@^3.0.0:
+  version "3.4.5"
+  resolved "https://registry.yarnpkg.com/js-base64/-/js-base64-3.4.5.tgz#6d1921e65a172cfd924604e1416dfaff45752c3e"
+  integrity sha512-Ub/AANierdcT8nm4ndBn3KzpZQ3MdHX4a+bwoVdjgeHCZ0ZEcP+UB4nmR4Z5lR6SH3Y+qAPmgVR0RxKJNHNHEg==
 
 js-sha256@^0.9.0:
   version "0.9.0"