diff --git a/CHANGES b/CHANGES
index b1b77b7d3c..0f425b65fa 100644
--- a/CHANGES
+++ b/CHANGES
@@ -1,3 +1,12 @@
+
+4.2.0-dev.240 | 2021-10-01 13:28:39 -0700
+
+  * Bump highwayhash submodule to pull in another FreeBSD header fix (Christian Kreibich, Corelight)
+
+  * CI tweak: upgrade curl on FreeBSD to avoid cert expiration (Christian Kreibich, Corelight)
+
+  * CI tweak: add a datestamp to Debian 9 Dockerfiles to invalidate Cirrus build cache (Christian Kreibich, Corelight)
+
 4.2.0-dev.235 | 2021-09-28 10:04:46 -0700
 
   * GHI-1766: Remove address from Site::private_address_space that converts into 0.0.0.0/0 (Tim Wojtulewicz, Corelight)
diff --git a/VERSION b/VERSION
index aa956a6205..f736e8a24d 100644
--- a/VERSION
+++ b/VERSION
@@ -1 +1 @@
-4.2.0-dev.235
+4.2.0-dev.240
diff --git a/auxil/highwayhash b/auxil/highwayhash
index 2361494e04..ca0ff296b1 160000
--- a/auxil/highwayhash
+++ b/auxil/highwayhash
@@ -1 +1 @@
-Subproject commit 2361494e0400d52eb76d2c6c62db72168ebe69d0
+Subproject commit ca0ff296b116354957276cef2c61be171ac2f897
diff --git a/ci/debian-9-32bit/Dockerfile b/ci/debian-9-32bit/Dockerfile
index 3a6990216d..a0078c3c30 100644
--- a/ci/debian-9-32bit/Dockerfile
+++ b/ci/debian-9-32bit/Dockerfile
@@ -2,6 +2,10 @@ FROM i386/debian:9
 
 ENV DEBIAN_FRONTEND="noninteractive" TZ="America/Los_Angeles"
 
+# A version field to invalide Cirrus's build cache when needed, as suggested in
+# https://github.com/cirruslabs/cirrus-ci-docs/issues/544#issuecomment-566066822
+ENV DOCKERFILE_VERSION 221001
+
 RUN apt-get update && apt-get -y install \
     git \
     cmake \
diff --git a/ci/debian-9/Dockerfile b/ci/debian-9/Dockerfile
index 2fcde5fc01..1087378337 100644
--- a/ci/debian-9/Dockerfile
+++ b/ci/debian-9/Dockerfile
@@ -2,6 +2,10 @@ FROM debian:9
 
 ENV DEBIAN_FRONTEND="noninteractive" TZ="America/Los_Angeles"
 
+# A version field to invalide Cirrus's build cache when needed, as suggested in
+# https://github.com/cirruslabs/cirrus-ci-docs/issues/544#issuecomment-566066822
+ENV DOCKERFILE_VERSION 221001
+
 RUN apt-get update && apt-get -y install \
     git \
     cmake \
diff --git a/ci/freebsd/prepare.sh b/ci/freebsd/prepare.sh
index 0ec60513cf..00b3965e2f 100755
--- a/ci/freebsd/prepare.sh
+++ b/ci/freebsd/prepare.sh
@@ -7,6 +7,7 @@ set -x
 
 env ASSUME_ALWAYS_YES=YES pkg bootstrap
 pkg install -y bash git cmake swig bison python3 base64
+pkg upgrade -y curl
 pyver=`python3 -c 'import sys; print(f"py{sys.version_info[0]}{sys.version_info[1]}")'`
 pkg install -y $pyver-sqlite3 $pyver-pip
 pip install junit2html