diff --git a/2.5/alpine3.7/Dockerfile b/2.5/alpine3.7/Dockerfile
index c21be0605..f91c6dfa0 100644
--- a/2.5/alpine3.7/Dockerfile
+++ b/2.5/alpine3.7/Dockerfile
@@ -11,7 +11,7 @@ ENV RUBY_MAJOR 2.5
 ENV RUBY_VERSION 2.5.1
 ENV RUBY_DOWNLOAD_SHA256 886ac5eed41e3b5fc699be837b0087a6a5a3d10f464087560d2d21b3e71b754d
 ENV RUBYGEMS_VERSION 2.7.7
-ENV BUNDLER_VERSION 1.16.3
+ENV BUNDLER_VERSION 1.16.4
 
 # some of ruby's build scripts are written in ruby
 #   we purge system ruby later to make sure our final image uses what we just built
diff --git a/2.5/stretch/Dockerfile b/2.5/stretch/Dockerfile
index 5fa1f0a74..09b8b676e 100644
--- a/2.5/stretch/Dockerfile
+++ b/2.5/stretch/Dockerfile
@@ -11,7 +11,7 @@ ENV RUBY_MAJOR 2.5
 ENV RUBY_VERSION 2.5.1
 ENV RUBY_DOWNLOAD_SHA256 886ac5eed41e3b5fc699be837b0087a6a5a3d10f464087560d2d21b3e71b754d
 ENV RUBYGEMS_VERSION 2.7.7
-ENV BUNDLER_VERSION 1.16.3
+ENV BUNDLER_VERSION 1.16.4
 
 # some of ruby's build scripts are written in ruby
 #   we purge system ruby later to make sure our final image uses what we just built
diff --git a/2.5/stretch/slim/Dockerfile b/2.5/stretch/slim/Dockerfile
index e853a6f76..a7f547b45 100644
--- a/2.5/stretch/slim/Dockerfile
+++ b/2.5/stretch/slim/Dockerfile
@@ -23,7 +23,7 @@ ENV RUBY_MAJOR 2.5
 ENV RUBY_VERSION 2.5.1
 ENV RUBY_DOWNLOAD_SHA256 886ac5eed41e3b5fc699be837b0087a6a5a3d10f464087560d2d21b3e71b754d
 ENV RUBYGEMS_VERSION 2.7.7
-ENV BUNDLER_VERSION 1.16.3
+ENV BUNDLER_VERSION 1.16.4
 
 # some of ruby's build scripts are written in ruby
 #   we purge system ruby later to make sure our final image uses what we just built