diff --git a/requirements.txt b/requirements.txt
index 7c1d923..97a1a2d 100644
--- a/requirements.txt
+++ b/requirements.txt
@@ -67,7 +67,7 @@ Jinja2==2.10.1
 jsonschema==3.1.1
 kombu==4.6.5
 lazy-object-proxy==1.4.2
-lxml==4.4.1
+lxml==4.6.3
 Mako==1.1.0
 MarkupSafe==1.1.1
 marshmallow==2.18.0