diff --git a/requirements.txt b/requirements.txt
index 716ec0e..a55ac1e 100644
--- a/requirements.txt
+++ b/requirements.txt
@@ -38,7 +38,7 @@ jupyter-client==5.2.4
 jupyter-console==6.0.0
 jupyter-core==4.4.0
 kiwisolver==1.1.0
-lxml==4.3.4
+lxml==4.9.1
 mammoth==1.4.9
 MarkupSafe==1.1.1
 matplotlib==3.1.0