diff --git a/fs/Dockerfile b/fs/Dockerfile
index b5e8f5d4..b40eee25 100644
--- a/fs/Dockerfile
+++ b/fs/Dockerfile
@@ -44,7 +44,7 @@ RUN apt-get update && \
         jq=1.6-2.1ubuntu3 \
         lua5.4=5.4.4-1 \
         lua-socket=3.0~rc1+git+ac3201d-6 \
-        xxd=2:8.2.3995-1ubuntu2.15 \
+        xxd=2:8.2.3995-1ubuntu2.16 \
         file=1:5.41-3ubuntu0.1 \
         /tmp/${TOOLS_DEB} \
         && \
diff --git a/sys-utils/cartesi-init/cartesi-init b/sys-utils/cartesi-init/cartesi-init
index 80b132f8..628d5ab5 100755
--- a/sys-utils/cartesi-init/cartesi-init
+++ b/sys-utils/cartesi-init/cartesi-init
@@ -35,7 +35,8 @@ fi
 
 # is entrypoint not empty?
 if [ -n "$ENTRYPOINT" ]; then
-    USER=${USER:-root}
+    # set default user to "dapp" if available, otherwise fallback to root
+    USER=${USER:-$(busybox id -un dapp 2>/dev/null || echo root)}
     HOME=$(eval echo ~$USER)
     WORKDIR=${WORKDIR:-"$HOME"}