diff --git a/Dockerfile b/Dockerfile
index 5ec7c0e3..ac2ae14f 100644
--- a/Dockerfile
+++ b/Dockerfile
@@ -1,4 +1,4 @@
-FROM ruby:2.3.1
+FROM ruby:2.3.4
 
 # app dependencies
 RUN apt-get update -qq && apt-get install -y build-essential libpq-dev nodejs
diff --git a/Dockerfile.dev b/Dockerfile.dev
index 6e4f9b70..90241e0a 100644
--- a/Dockerfile.dev
+++ b/Dockerfile.dev
@@ -1,4 +1,4 @@
-FROM ruby:2.3.1
+FROM ruby:2.3.4
 
 # app dependencies
 RUN apt-get update -qq && apt-get install -y build-essential libpq-dev nodejs
diff --git a/Gemfile b/Gemfile
index 75554816..ef04d15c 100644
--- a/Gemfile
+++ b/Gemfile
@@ -1,6 +1,6 @@
 source 'https://rubygems.org'
 
-ruby '2.3.1'
+ruby '2.3.4'
 
 # Bundle edge Rails instead: gem 'rails', github: 'rails/rails'
 gem 'rails', '~> 5.0.0', '>= 5.0.0.1'
diff --git a/Gemfile.lock b/Gemfile.lock
index 999bd378..9b37b4ff 100644
--- a/Gemfile.lock
+++ b/Gemfile.lock
@@ -256,7 +256,7 @@ DEPENDENCIES
   web-console
 
 RUBY VERSION
-   ruby 2.3.1p112
+   ruby 2.3.4p301
 
 BUNDLED WITH
-   1.13.6
+   1.14.6