diff --git a/back/requirements.txt b/back/requirements.txt
index 4d9e1d5..15d1850 100644
--- a/back/requirements.txt
+++ b/back/requirements.txt
@@ -22,7 +22,7 @@ intervaltree==2.1.0
 itypes==1.1.0
 Jinja2==2.11.3
 kombu==4.2.2.post1
-lxml==4.6.3
+lxml==4.9.1
 Markdown==3.0.1
 MarkupSafe==1.1.0
 psycopg2-binary==2.7.6.1