diff --git a/requirements.txt b/requirements.txt
index 41dd98a..9159960 100644
--- a/requirements.txt
+++ b/requirements.txt
@@ -13,7 +13,7 @@ idna==2.8
 itsdangerous==1.1.0
 Jinja2==2.10.1
 joblib==0.13.2
-lxml==4.3.3
+lxml==4.9.1
 MarkupSafe==1.1.1
 numpy==1.16.4
 oauthlib==3.0.1