diff --git a/requirements.txt b/requirements.txt
index 14bdf18..4856151 100644
--- a/requirements.txt
+++ b/requirements.txt
@@ -29,7 +29,7 @@ jupyter-console==6.0.0
 jupyter-core==4.4.0
 kiwisolver==1.0.1
 lazy-object-proxy==1.3.1
-lxml==4.3.1
+lxml==4.9.1
 MarkupSafe==1.1.1
 matplotlib==3.0.3
 mccabe==0.6.1