diff --git a/requirements.txt b/requirements.txt
index feb2941..9f4638d 100644
--- a/requirements.txt
+++ b/requirements.txt
@@ -29,7 +29,7 @@ jupyter-core==4.6.3
 jupyterlab==2.1.4
 jupyterlab-server==1.1.5
 kiwisolver==1.2.0
-lxml==4.6.2
+lxml==4.9.1
 MarkupSafe==1.1.1
 matplotlib==3.2.1
 mistune==0.8.4