diff --git a/Gemfile.lock b/Gemfile.lock
index 8fb39a8..3f0075e 100644
--- a/Gemfile.lock
+++ b/Gemfile.lock
@@ -14,8 +14,8 @@ GEM
       i18n (>= 0.7, < 2)
       minitest (~> 5.1)
       tzinfo (~> 1.1)
-    addressable (2.6.0)
-      public_suffix (>= 2.0.2, < 4.0)
+    addressable (2.8.1)
+      public_suffix (>= 2.0.2, < 6.0)
     ast (2.4.0)
     backport (1.1.2)
     childprocess (1.0.1)
@@ -57,7 +57,7 @@ GEM
     parser (2.6.3.0)
       ast (~> 2.4.0)
     plissken (1.3.0)
-    public_suffix (3.1.1)
+    public_suffix (5.0.0)
     rainbow (3.0.0)
     rake (10.5.0)
     reverse_markdown (1.1.0)