diff --git a/requirements.txt b/requirements.txt
index 6cea687..6fca3dc 100644
--- a/requirements.txt
+++ b/requirements.txt
@@ -15,7 +15,7 @@ idna==2.6
 itsdangerous==0.24
 jdcal==1.3
 Jinja2==2.10
-lxml==4.2.1
+lxml==4.9.1
 MarkupSafe==1.0
 odfpy==1.3.6
 openpyxl==2.5.1