diff --git a/ci/docker/buildenv/Dockerfile b/ci/docker/buildenv/Dockerfile
index d5e56df3c..27a58073a 100644
--- a/ci/docker/buildenv/Dockerfile
+++ b/ci/docker/buildenv/Dockerfile
@@ -59,7 +59,7 @@ RUN . /tmp/wavetools.conf && \
     wget -q ${WGET_EXTRA_ARGS} -O /tmp/wavetools.tar.gz \
     "https://github.com/hudson-trading/wavetools/releases/download/${WAVETOOLS_VERSION}/wavetools-${WAVETOOLS_VERSION}-linux-x86_64.tar.gz" && \
     tar -xzf /tmp/wavetools.tar.gz -C /tmp && \
-    cp /tmp/wavetools-${WAVETOOLS_VERSION}-linux-x86_64/wavediff /usr/local/bin/wavediff && \
+    cp -p /tmp/wavetools-${WAVETOOLS_VERSION}-linux-x86_64/wavediff /usr/local/bin/wavediff && \
     rm -rf /tmp/wavetools.tar.gz /tmp/wavetools-* /tmp/wavetools.conf
 
 COPY build.sh /tmp/build.sh