diff --git a/autoconf/Dockerfile b/autoconf/Dockerfile
index 1108f4c..be4dfd4 100644
--- a/autoconf/Dockerfile
+++ b/autoconf/Dockerfile
@@ -5,7 +5,7 @@ ARG AUTOCONF_ARCHIVE_VERSION="2023.02.20"
 ARG AUTOMAKE_VERSION="1.16.5"
 
 LABEL org.opencontainers.image.source="https://github.com/python/cpython-devcontainers"
-LABEL org.opencontainers.image.base.name="docker.io/library/alpine:3.19"
+LABEL org.opencontainers.image.base.name="docker.io/library/ubuntu:22.04"
 LABEL org.opencontainers.image.authors="Donghee Na"
 LABEL org.opencontainers.image.title="GNU Autoconf ${AUTOCONF_VERSION} container for CPython"
 LABEL org.opencontainers.image.description="Container image with GNU Autoconf ${AUTOCONF_VERSION}, GNU Automake ${AUTOMAKE_VERSION}, and autoconf-archive ${AUTOCONF_ARCHIVE_VERSION} for generating CPython's configure script."
diff --git a/autoconf/entry.sh b/autoconf/entry.sh
index 81c50ed..4069e46 100755
--- a/autoconf/entry.sh
+++ b/autoconf/entry.sh
@@ -1,6 +1,8 @@
 #!/bin/sh
 set -e
 
+export CONFIG_SHELL="/usr/bin/bash"
+
 BIN=/usr/local/bin
 AUTOCONF=$BIN/autoconf
 AUTORECONF=$BIN/autoreconf