diff --git a/requirements.txt b/requirements.txt
index 434b590..dab22a2 100644
--- a/requirements.txt
+++ b/requirements.txt
@@ -12,7 +12,7 @@ gunicorn==19.9.0
 idna==2.8
 joblib==0.13.2
 kiwisolver==1.1.0
-lxml==4.3.3
+lxml==4.9.1
 matplotlib==3.1.0
 numpy==1.15.4
 pandas==0.23.4