diff --git a/CHANGELOG.md b/CHANGELOG.md
index 0cafb8ec3a..4149e83b2c 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -8,6 +8,7 @@ See the [releases page](https://github.com/github/codeql-action/releases) for th
   The `actions` extractor has been included in the CodeQL CLI since v2.20.6. If your workflow has enabled the `actions` language _and_ you have pinned
   your `tools:` property to a specific version of the CodeQL CLI earlier than v2.20.6, you will need to update to at least CodeQL v2.20.6 or disable
   `actions` analysis.
+- Update default CodeQL bundle version to 2.21.4. [#2910](https://github.com/github/codeql-action/pull/2910)
 
 ## 3.28.18 - 16 May 2025
 
diff --git a/lib/defaults.json b/lib/defaults.json
index 74df6ad6d2..1fd91fd50c 100644
--- a/lib/defaults.json
+++ b/lib/defaults.json
@@ -1,6 +1,6 @@
 {
-    "bundleVersion": "codeql-bundle-v2.21.3",
-    "cliVersion": "2.21.3",
-    "priorBundleVersion": "codeql-bundle-v2.21.2",
-    "priorCliVersion": "2.21.2"
+    "bundleVersion": "codeql-bundle-v2.21.4",
+    "cliVersion": "2.21.4",
+    "priorBundleVersion": "codeql-bundle-v2.21.3",
+    "priorCliVersion": "2.21.3"
 }
diff --git a/src/defaults.json b/src/defaults.json
index 8232e77e30..e2cd3f08e3 100644
--- a/src/defaults.json
+++ b/src/defaults.json
@@ -1,6 +1,6 @@
 {
-  "bundleVersion": "codeql-bundle-v2.21.3",
-  "cliVersion": "2.21.3",
-  "priorBundleVersion": "codeql-bundle-v2.21.2",
-  "priorCliVersion": "2.21.2"
+  "bundleVersion": "codeql-bundle-v2.21.4",
+  "cliVersion": "2.21.4",
+  "priorBundleVersion": "codeql-bundle-v2.21.3",
+  "priorCliVersion": "2.21.3"
 }