diff --git a/installer/Dockerfile b/installer/Dockerfile
index 6636d9baa..d5823ec0f 100644
--- a/installer/Dockerfile
+++ b/installer/Dockerfile
@@ -18,7 +18,7 @@ RUN apt-get update && \
 COPY . /opt/maxkb/app
 RUN mkdir -p /opt/maxkb/app /opt/maxkb/model /opt/maxkb/conf && \
     rm -rf /opt/maxkb/app/ui && \
-    useradd sandbox && mkdir /opt/maxkb/app/sandbox && chown sandbox:sandbox /opt/maxkb/app/sandbox && chmod 700 /opt/maxkb/app/sandbox
+    useradd -m sandbox && mkdir /opt/maxkb/app/sandbox && chown sandbox:sandbox /opt/maxkb/app/sandbox && chmod 700 /opt/maxkb/app/sandbox
 
 COPY --from=web-build ui /opt/maxkb/app/ui
 WORKDIR /opt/maxkb/app