diff --git a/docker/Dockerfile.fluke b/docker/Dockerfile.fluke
index 0956e98..cfd507e 100644
--- a/docker/Dockerfile.fluke
+++ b/docker/Dockerfile.fluke
@@ -55,7 +55,7 @@ RUN set -ex \
 		zlib-dev \
 		xz
 
-RUN wget -O ruby.tar.xz "https://cache.ruby-lang.org/pub/ruby/2.3/ruby-2.3.1.tar.xz" \
+RUN wget -O ruby.tar.xz "https://cache.ruby-lang.org/pub/ruby/2.3/ruby-2.3.5.tar.xz" \
 	# && echo "$RUBY_DOWNLOAD_SHA256 *ruby.tar.xz" | sha256sum -c - \
 	\
 	&& mkdir -p /usr/src/ruby \