diff --git a/docs/Gemfile.lock b/docs/Gemfile.lock
index 540a0c302..22f8d4e19 100644
--- a/docs/Gemfile.lock
+++ b/docs/Gemfile.lock
@@ -19,7 +19,7 @@ GEM
     execjs (2.6.0)
     faraday (0.9.2)
       multipart-post (>= 1.2, < 3)
-    ffi (1.9.10)
+    ffi (1.13.1)
     gemoji (2.1.0)
     github-pages (45)
       RedCloth (= 4.2.9)