diff --git a/requirements.txt b/requirements.txt
index 3342705..d8bc469 100644
--- a/requirements.txt
+++ b/requirements.txt
@@ -106,7 +106,7 @@ testpath==0.4.4
 threadpoolctl==2.1.0
 tifffile==2020.6.3
 toml==0.10.1
-tornado==6.0.4
+tornado==6.4.2
 traitlets==4.3.3
 typed-ast==1.4.1
 urllib3==1.25.9