diff --git a/CHANGELOG.md b/CHANGELOG.md
index 3917630f..8f998cde 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -1,5 +1,13 @@
 # Changelog
 
+## [1.42.1](https://github.com/googleworkspace/apps-script-oauth2/compare/v1.42.0...v1.42.1) (2022-09-23)
+
+
+### Bug Fixes
+
+* Remove use of 'let' for Rhino compatibility ([f6fdc9a](https://github.com/googleworkspace/apps-script-oauth2/commit/f6fdc9ac98bb4c099c002c60b1a5ddced66f95f1))
+* Remove use of 'let' for Rhino compatibility ([089a3e4](https://github.com/googleworkspace/apps-script-oauth2/commit/089a3e4af8c06b82156e76ef2b78b5f202a0a0e5))
+
 ## 1.42.0 (2022-09-22)
 
 ### Features
diff --git a/package-lock.json b/package-lock.json
index 4928b994..18506749 100644
--- a/package-lock.json
+++ b/package-lock.json
@@ -1,12 +1,12 @@
 {
   "name": "apps-script-oauth2",
-  "version": "1.42.0",
+  "version": "1.42.1",
   "lockfileVersion": 2,
   "requires": true,
   "packages": {
     "": {
       "name": "apps-script-oauth2",
-      "version": "1.42.0",
+      "version": "1.42.1",
       "license": "Apache-2.0",
       "devDependencies": {
         "@google/clasp": "2.4.1",
diff --git a/package.json b/package.json
index 60f34607..d537b686 100644
--- a/package.json
+++ b/package.json
@@ -1,6 +1,6 @@
 {
   "name": "apps-script-oauth2",
-  "version": "1.42.0",
+  "version": "1.42.1",
   "description": "OAuth2 for Apps Script is a library for Google Apps Script that provides the ability to create and authorize OAuth2 tokens as well as refresh them when they expire.",
   "repository": {
     "type": "git",
diff --git a/src/Service.js b/src/Service.js
index f16bd45c..119ee5a4 100644
--- a/src/Service.js
+++ b/src/Service.js
@@ -140,7 +140,7 @@ Service_.prototype.setCodeVerififer = function(codeVerifier) {
  */
 Service_.prototype.generateCodeVerifier = function() {
   const rawBytes = [];
-  for (let i = 0; i < 32; ++i) {
+  for (var i = 0; i < 32; ++i) {
     const r = Math.floor(Math.random() * 255);
     rawBytes[i] = r;
   }
diff --git a/src/Utilities.js b/src/Utilities.js
index dfcbd0fc..c39a88fb 100644
--- a/src/Utilities.js
+++ b/src/Utilities.js
@@ -137,7 +137,7 @@ function decodeJwt_(jwt) {
  * @return {string} Web safe base64 encoded with padding removed.
  */
 function encodeUrlSafeBase64NoPadding_(value) {
-  let encodedValue = Utilities.base64EncodeWebSafe(value);
+  var encodedValue = Utilities.base64EncodeWebSafe(value);
   encodedValue = encodedValue.slice(0, encodedValue.indexOf('='));
   return encodedValue;
 }