diff --git a/requirements.txt b/requirements.txt
index 3d91f70..f0c0345 100644
--- a/requirements.txt
+++ b/requirements.txt
@@ -37,7 +37,7 @@ joblib==0.17.0
 kiwisolver==1.3.0
 konoha==4.6.2
 langdetect==1.0.8
-lxml==4.6.1
+lxml==4.9.1
 Markdown==3.3.3
 MarkupSafe==1.1.1
 matplotlib==3.3.2