diff --git a/documentation/requirements.txt b/documentation/requirements.txt
index 3ad67fae..19c83b44 100644
--- a/documentation/requirements.txt
+++ b/documentation/requirements.txt
@@ -19,7 +19,7 @@ six==1.13.0
 smartypants==2.0.1
 smmap2==2.0.5
 soupsieve==1.9.5
-tornado==6.0.3
+tornado==6.4.1
 typogrify==2.0.7
 Unidecode==1.1.1
 webassets==0.12.1