diff --git a/Dockerfile b/Dockerfile
index 62c0431..111c2f6 100644
--- a/Dockerfile
+++ b/Dockerfile
@@ -1,4 +1,4 @@
-FROM ruby:2.3.6-slim
+FROM ruby:2.5.3-slim
 
 RUN apt-get update -qq && apt-get install -y \
     apt-transport-https \
@@ -21,7 +21,7 @@ RUN apt-get update -qq && apt-get install -y \
 RUN gem update
 
 RUN sed -i 's/\(:DoNotReverseLookup *=> *\).*\(,\)/\1true\2/g' \
-           /usr/local/lib/ruby/2.3.0/webrick/config.rb
+           /usr/local/lib/ruby/2.5.0/webrick/config.rb
 
 RUN apt-get clean
 
diff --git a/README.md b/README.md
index 0017d73..62eb2b1 100644
--- a/README.md
+++ b/README.md
@@ -2,7 +2,7 @@
 
 Docker image with Ruby, Node.js, and Yarn, plus some PostgreSQL related packages, and the tools to build native Gems for Rails.
 
-Docker image with Ruby 2.3.6, based on official [ruby:2.3.6-slim](https://hub.docker.com/_/ruby/) image.
+Docker image with Ruby 2.5.3, based on official [ruby:2.5.3-slim](https://hub.docker.com/_/ruby/) image.
 
 **Docker Hub:** [setanta/ruby-nodejs-pgclient](https://hub.docker.com/r/setanta/ruby-nodejs-pgclient/)