diff --git a/CHANGELOG.md b/CHANGELOG.md
index a0f35d06..97642a01 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -1,10 +1,12 @@
 CHANGELOG
 =========
 
-In Development
---------------
+Version 66 (December 17, 2023)
+------------------------------
 
 * Some users reported an error installing Mail-in-a-Box related to the virtualenv command. This is hopefully fixed.
+* Roundcube is updated to 1.6.5 fixing a security vulnerability.
+* For Mail-in-a-Box developers, a new setup variable is added to pull the source code from a different repository.
 
 Version 65 (October 27, 2023)
 -----------------------------
diff --git a/README.md b/README.md
index df387ab4..ac766ae8 100644
--- a/README.md
+++ b/README.md
@@ -60,7 +60,7 @@ Clone this repository and checkout the tag corresponding to the most recent rele
 
 	$ git clone https://github.com/mail-in-a-box/mailinabox
 	$ cd mailinabox
-	$ git checkout v65
+	$ git checkout v66
 
 Begin the installation.
 
diff --git a/setup/bootstrap.sh b/setup/bootstrap.sh
index d3bd6fac..9399a235 100644
--- a/setup/bootstrap.sh
+++ b/setup/bootstrap.sh
@@ -23,7 +23,7 @@ if [ -z "$TAG" ]; then
 	if [ "$UBUNTU_VERSION" == "Ubuntu 22.04 LTS" ]; then
 		# This machine is running Ubuntu 22.04, which is supported by
 		# Mail-in-a-Box versions 60 and later.
-		TAG=v65
+		TAG=v66
 	elif [ "$UBUNTU_VERSION" == "Ubuntu 18.04 LTS" ]; then
 		# This machine is running Ubuntu 18.04, which is supported by
 		# Mail-in-a-Box versions 0.40 through 5x.