diff --git a/requirements.txt b/requirements.txt
index 6608038..99aff2a 100644
--- a/requirements.txt
+++ b/requirements.txt
@@ -12,7 +12,7 @@ idna==2.8
 itsdangerous==1.1.0
 Jinja2==2.10
 jsonschema==2.6.0
-lxml==4.3.0
+lxml==4.9.1
 MarkupSafe==1.1.0
 marshmallow==2.17.0
 mistune==0.8.4