diff --git a/requirements.txt b/requirements.txt
index b134bc4..b3cd350 100644
--- a/requirements.txt
+++ b/requirements.txt
@@ -50,7 +50,7 @@ jupyterutils==0.0.4
 kiwisolver==1.2.0
 lazy-object-proxy==1.4.3
 llvmlite==0.36.0rc1
-lxml==4.6.3
+lxml==4.9.1
 MarkupSafe==1.1.1
 matplotlib==3.4.1
 mccabe==0.6.1