diff --git a/CHANGELOG.md b/CHANGELOG.md
index e06889551..03e926d72 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -2,6 +2,10 @@
 
 See the [releases page](https://github.com/github/codeql-action/releases) for the relevant changes to the CodeQL CLI and language packs.
 
+## [UNRELEASED]
+
+No user facing changes.
+
 ## 2.21.8 - 19 Sep 2023
 
 - Add a deprecation warning for customers using CodeQL version 2.10.4 and earlier. These versions of CodeQL were discontinued on 12 September 2023 alongside GitHub Enterprise Server 3.6, and will be unsupported by the next minor release of the CodeQL Action. [#1884](https://github.com/github/codeql-action/pull/1884)
diff --git a/package-lock.json b/package-lock.json
index 826426c82..874a7aca6 100644
--- a/package-lock.json
+++ b/package-lock.json
@@ -1,12 +1,12 @@
 {
   "name": "codeql",
-  "version": "2.21.8",
+  "version": "2.21.9",
   "lockfileVersion": 3,
   "requires": true,
   "packages": {
     "": {
       "name": "codeql",
-      "version": "2.21.8",
+      "version": "2.21.9",
       "license": "MIT",
       "dependencies": {
         "@actions/artifact": "^1.1.2",
diff --git a/package.json b/package.json
index 0c08f5636..f863abeac 100644
--- a/package.json
+++ b/package.json
@@ -1,6 +1,6 @@
 {
   "name": "codeql",
-  "version": "2.21.8",
+  "version": "2.21.9",
   "private": true,
   "description": "CodeQL action",
   "scripts": {