diff --git a/requirements.txt b/requirements.txt
index d45517f..a5ee2ed 100644
--- a/requirements.txt
+++ b/requirements.txt
@@ -10,7 +10,7 @@ itsdangerous==0.24
 Jinja2==2.11.1
 ldap3==2.5.1
 html5lib==1.0.1
-lxml==4.2.4
+lxml==4.9.1
 MarkupSafe==1.0
 pyasn1==0.4.4
 pyasn1-modules==0.2.2