diff --git a/Dockerfile b/Dockerfile
index 573142ce..f9ad88b3 100644
--- a/Dockerfile
+++ b/Dockerfile
@@ -7,8 +7,9 @@ WORKDIR "/opt"
 
 ENV GRAALVM_VERSION="22.3.0"
 ARG TARGETARCH
-ENV BABASHKA_ARCH=${TARGETARCH}
-ENV GRAALVM_ARCH=${TARGETARCH}
+# Do not set those directly, use TARGETARCH instead
+ENV BABASHKA_ARCH=
+ENV GRAALVM_ARCH=
 RUN if [ "${TARGETARCH}" = "" ] || [ "${TARGETARCH}" = "amd64" ]; then \
       export GRAALVM_ARCH=amd64; export BABASHKA_ARCH=x86_64; \
     elif [ "${TARGETARCH}" = "arm64" ]; then \
diff --git a/script/setup-musl b/script/setup-musl
index ad055064..dcb552e5 100755
--- a/script/setup-musl
+++ b/script/setup-musl
@@ -19,8 +19,8 @@ fi
 
 apt-get update -y && apt-get install musl-tools -y
 
-ZLIB_VERSION="1.2.11"
-ZLIB_SHA256="c3e5e9fdd5004dcb542feda5ee4f0ff0744628baf8ed2dd5d66f8ca1197cb1a1"
+ZLIB_VERSION="1.2.13"
+ZLIB_SHA256="b3a24de97a8fdbc835b9833169501030b8977031bcb54b3b3ac13740f846ab30"
 
 # stable archive path
 curl -O -sL --fail --show-error "https://zlib.net/fossils/zlib-${ZLIB_VERSION}.tar.gz"