diff --git a/build/Dockerfile b/build/Dockerfile
index 1413f383..5bf7a20f 100644
--- a/build/Dockerfile
+++ b/build/Dockerfile
@@ -88,7 +88,7 @@ RUN apt-get update -qq \
 
 WORKDIR /downloads
 
-RUN curl -Ls https://raw.githubusercontent.com/gotenberg/unoconverter/v0.3.0/unoconv -o unoconverter \
+RUN curl -Ls https://raw.githubusercontent.com/gotenberg/unoconverter/v0.4.0/unoconv -o unoconverter \
     && chmod +x unoconverter
 
 RUN curl -o pdftk-all.jar "https://gitlab.com/api/v4/projects/5024297/packages/generic/pdftk-java/$PDFTK_VERSION/pdftk-all.jar" \