diff --git a/requirements.txt b/requirements.txt
index 1ec89bd..9c1b81c 100644
--- a/requirements.txt
+++ b/requirements.txt
@@ -41,7 +41,7 @@ jmespath==0.10.0
 jsonschema==3.0.2
 jupyter-core==4.5.0
 kappa==0.6.0
-lxml==4.4.1
+lxml==4.9.1
 Mako==1.1.0
 MarkupSafe==1.1.1
 mccabe==0.6.1