diff --git a/Gemfile.lock b/Gemfile.lock
index 459380bf..30959b9a 100644
--- a/Gemfile.lock
+++ b/Gemfile.lock
@@ -262,6 +262,8 @@ GEM
       pry (~> 0.13.0)
     pry-rails (0.3.9)
       pry (>= 0.10.4)
+    psych (4.0.3)
+      stringio
     public_suffix (4.0.6)
     puma (5.3.0)
       nio4r (~> 2.0)
@@ -299,7 +301,8 @@ GEM
     rb-inotify (0.10.1)
       ffi (~> 1.0)
     rchardet (1.8.0)
-    rdoc (6.3.0)
+    rdoc (6.4.0)
+      psych (>= 4.0.0)
     regexp_parser (2.0.3)
     responders (2.4.1)
       actionpack (>= 4.2.0, < 6.0)
@@ -363,7 +366,7 @@ GEM
     scrub_rb (1.0.1)
     scss_lint (0.59.0)
       sass (~> 3.5, >= 3.5.5)
-    sdoc (2.1.0)
+    sdoc (2.3.2)
       rdoc (>= 5.0)
     selenium-webdriver (3.142.7)
       childprocess (>= 0.5, < 4.0)
@@ -392,6 +395,7 @@ GEM
       activesupport (>= 4.0)
       sprockets (>= 3.0.0)
     stomp (1.4.8)
+    stringio (3.0.1)
     terminal-table (3.0.0)
       unicode-display_width (~> 1.1, >= 1.1.1)
     thor (1.1.0)