diff --git a/requirements.txt b/requirements.txt
index f4eaa62..10ce6a3 100644
--- a/requirements.txt
+++ b/requirements.txt
@@ -91,7 +91,7 @@ jupyterlab-pygments==0.1.2
 jupyter-dash
 kiwisolver==1.2.0
 lazy-object-proxy==1.4.3
-lxml==4.6.5
+lxml==4.9.1
 MarkupSafe==1.1.1
 matplotlib==3.3.2
 mccabe==0.6.1