diff --git a/requirements.txt b/requirements.txt
index cdb6744..950c335 100644
--- a/requirements.txt
+++ b/requirements.txt
@@ -42,7 +42,7 @@ keyrings.alt==3.1.1
 kiwisolver==1.0.1
 lazy-object-proxy==1.3.1
 logilab-common==1.4.2
-lxml==4.6.5
+lxml==4.9.1
 MarkupSafe==1.1.0
 matplotlib==3.0.2
 mccabe==0.6.1