diff --git a/requirements.txt b/requirements.txt
index 36b78f3..d97d2ea 100644
--- a/requirements.txt
+++ b/requirements.txt
@@ -23,7 +23,7 @@ launchpadlib==1.10.6
 lazr.restfulclient==0.13.5
 lazr.uri==1.0.3
 louis==3.5.0
-lxml==4.3.1
+lxml==4.9.1
 macaroonbakery==1.1.3
 Mako==1.0.7
 MarkupSafe==1.0