diff --git a/requirements.txt b/requirements.txt
index e74d65b..3d5082a 100644
--- a/requirements.txt
+++ b/requirements.txt
@@ -102,7 +102,7 @@ lazy-object-proxy==1.4.1
 libarchive-c==2.8
 llvmlite==0.29.0
 locket==0.2.0
-lxml==4.3.4
+lxml==4.9.1
 Markdown==3.1.1
 MarkupSafe==1.1.1
 matplotlib==3.1.0