diff --git a/kdav/Dockerfile b/kdav/Dockerfile
index b111e85..29b2a79 100644
--- a/kdav/Dockerfile
+++ b/kdav/Dockerfile
@@ -30,7 +30,7 @@ LABEL maintainer=az@zok.xyz \
     org.label-schema.schema-version="1.0"
 
 # install Kopano kDAV
-RUN \
+RUN --mount=type=secret,id=repocred,target=/etc/apt/auth.conf.d/kopano.conf \
     set -x && \
     apt-get update && apt-get install -y --no-install-recommends \
         php-mbstring \
@@ -62,4 +62,4 @@ ENTRYPOINT ["/usr/bin/dumb-init", "--"]
 CMD [ "/kopano/start.sh" ]
 
 ARG VCS_REF
-LABEL org.label-schema.vcs-ref=$VCS_REF
\ No newline at end of file
+LABEL org.label-schema.vcs-ref=$VCS_REF