diff --git a/requirements.txt b/requirements.txt
index 23470bf..83693f5 100644
--- a/requirements.txt
+++ b/requirements.txt
@@ -5,7 +5,7 @@ gunicorn==19.9.0
 numpy==1.16.4
 Pillow==6.2.0
 Twisted[tls,http2]==19.2.1
-lxml==4.2.1
+lxml==4.9.1
 cryptography==2.3
 asgiref==3.1.2
 cffi==1.11.2