diff --git a/Gemfile b/Gemfile
index e93a940c5..852a3aec0 100644
--- a/Gemfile
+++ b/Gemfile
@@ -67,7 +67,7 @@ group :development, :test do
   gem 'rubocop-rspec', '1.15.1'
   gem 'unicorn', '~> 5.3.0'
   gem 'rspec_junit_formatter', '~> 0.2.3'
-  gem 'poltergeist', '1.15.0'
+  gem 'poltergeist', '1.18.0'
 end
 
 group :staging do
diff --git a/Gemfile.lock b/Gemfile.lock
index 617bd7d32..fbd5f898c 100644
--- a/Gemfile.lock
+++ b/Gemfile.lock
@@ -67,7 +67,8 @@ GEM
       minitest (~> 5.1)
       thread_safe (~> 0.3, >= 0.3.4)
       tzinfo (~> 1.1)
-    addressable (2.4.0)
+    addressable (2.5.2)
+      public_suffix (>= 2.0.2, < 4.0)
     airbrussh (1.2.0)
       sshkit (>= 1.6.1, != 1.7.0)
     arel (6.0.4)
@@ -107,7 +108,7 @@ GEM
     capistrano-rbenv (2.1.1)
       capistrano (~> 3.1)
       sshkit (~> 1.3)
-    capybara (2.14.0)
+    capybara (2.14.4)
       addressable
       mime-types (>= 1.16)
       nokogiri (>= 1.3.3)
@@ -252,8 +253,8 @@ GEM
     parslet (1.7.1)
       blankslate (>= 2.0, <= 4.0)
     pg (0.18.3)
-    poltergeist (1.15.0)
-      capybara (~> 2.1)
+    poltergeist (1.18.0)
+      capybara (>= 2.1, < 4)
       cliver (~> 0.3.1)
       websocket-driver (>= 0.2.0)
     powerpack (0.1.1)
@@ -261,6 +262,7 @@ GEM
       coderay (~> 1.1.0)
       method_source (~> 0.8.1)
       slop (~> 3.4)
+    public_suffix (3.0.2)
     qa (1.1.0)
       activerecord-import
       deprecation
@@ -268,7 +270,7 @@ GEM
       nokogiri (~> 1.6)
       rails (>= 4.2.0, < 6.0)
       rdf
-    rack (1.6.8)
+    rack (1.6.10)
     rack-dev-mark (0.7.5)
       rack (>= 1.1)
     rack-test (0.6.3)
@@ -430,11 +432,11 @@ GEM
     warden (1.2.6)
       rack (>= 1.0)
     websocket (1.2.4)
-    websocket-driver (0.6.5)
+    websocket-driver (0.7.0)
       websocket-extensions (>= 0.1.0)
-    websocket-extensions (0.1.2)
+    websocket-extensions (0.1.3)
     xml-simple (1.1.5)
-    xpath (2.0.0)
+    xpath (2.1.0)
       nokogiri (~> 1.3)
 
 PLATFORMS
@@ -468,7 +470,7 @@ DEPENDENCIES
   nokogiri (= 1.8.2)
   omniauth (~> 1.7.1)
   omniauth-shibboleth (~> 1.2.1)
-  poltergeist (= 1.15.0)
+  poltergeist (= 1.18.0)
   pry (~> 0.10.4)
   qa (~> 1.1.0)
   rack-dev-mark (~> 0.7.5)