diff --git a/doc/tech-docs/Gemfile.lock b/doc/tech-docs/Gemfile.lock
index b387d6c3c4..9fdb19f88e 100644
--- a/doc/tech-docs/Gemfile.lock
+++ b/doc/tech-docs/Gemfile.lock
@@ -145,8 +145,7 @@ GEM
     rb-inotify (0.10.1)
       ffi (~> 1.0)
     redcarpet (3.5.1)
-    rexml (3.3.6)
-      strscan
+    rexml (3.3.9)
     rouge (3.30.0)
     sass (3.4.25)
     sassc (2.4.0)
@@ -155,7 +154,6 @@ GEM
     sprockets (4.2.0)
       concurrent-ruby (~> 1.0)
       rack (>= 2.2.4, < 4)
-    strscan (3.1.0)
     temple (0.10.0)
     thor (1.2.1)
     tilt (2.0.11)