diff --git a/requirements.txt b/requirements.txt
index 177b890..bf9385e 100644
--- a/requirements.txt
+++ b/requirements.txt
@@ -54,7 +54,7 @@ joblib==0.6.4
 kombu==2.1.8
 lazy-object-proxy==1.2.2
 louis==2.4.1
-lxml==2.3.2
+lxml==4.9.1
 mailer==0.7
 mccabe==0.6.1
 msgpack-python==0.1.10