diff --git a/Gemfile.lock b/Gemfile.lock
index 340498c..b26504d 100644
--- a/Gemfile.lock
+++ b/Gemfile.lock
@@ -192,7 +192,7 @@ GEM
     minitest (5.25.4)
     mocha (2.7.1)
       ruby2_keywords (>= 0.0.5)
-    msgpack (1.7.5)
+    msgpack (1.8.0)
     net-http (0.6.0)
       uri
     net-imap (0.5.5)
@@ -501,7 +501,7 @@ CHECKSUMS
   mini_mime (1.1.5) sha256=8681b7e2e4215f2a159f9400b5816d85e9d8c6c6b491e96a12797e798f8bccef
   minitest (5.25.4) sha256=9cf2cae25ac4dfc90c988ebc3b917f53c054978b673273da1bd20bcb0778f947
   mocha (2.7.1) sha256=8f7d538d5d3ebc75fc788b3d92fbab913a93a78462d2a3ce99d1bdde7af7f851
-  msgpack (1.7.5) sha256=ffb04979f51e6406823c03abe50e1da2c825c55a37dee138518cdd09d9d3aea8
+  msgpack (1.8.0) sha256=e64ce0212000d016809f5048b48eb3a65ffb169db22238fb4b72472fecb2d732
   net-http (0.6.0) sha256=9621b20c137898af9d890556848c93603716cab516dc2c89b01a38b894e259fb
   net-imap (0.5.5) sha256=abe6a8932c68269804b0f0b499a0d1972098e7e6b8b61a7c508b127ebde1682a
   net-pop (0.1.2) sha256=848b4e982013c15b2f0382792268763b748cce91c9e91e36b0f27ed26420dff3