diff --git a/week4/sample_app/Gemfile.lock b/week4/sample_app/Gemfile.lock
index 195e725..4f9eb21 100644
--- a/week4/sample_app/Gemfile.lock
+++ b/week4/sample_app/Gemfile.lock
@@ -57,7 +57,7 @@ GEM
       execjs
     coffee-script-source (1.12.2)
     concurrent-ruby (1.1.5)
-    crass (1.0.4)
+    crass (1.0.5)
     erubi (1.8.0)
     execjs (2.7.0)
     ffi (1.10.0)
@@ -90,7 +90,7 @@ GEM
       rb-fsevent (~> 0.9, >= 0.9.4)
       rb-inotify (~> 0.9, >= 0.9.7)
       ruby_dep (~> 1.2)
-    loofah (2.2.3)
+    loofah (2.3.1)
       crass (~> 1.0.2)
       nokogiri (>= 1.5.9)
     lumberjack (1.0.13)
@@ -108,7 +108,7 @@ GEM
     multi_json (1.13.1)
     nenv (0.3.0)
     nio4r (2.3.1)
-    nokogiri (1.10.2)
+    nokogiri (1.10.5)
       mini_portile2 (~> 2.4.0)
     notiffany (0.1.1)
       nenv (~> 0.1)