diff --git a/requirements.txt b/requirements.txt
index f1d36c7..ebf99c5 100644
--- a/requirements.txt
+++ b/requirements.txt
@@ -8,7 +8,7 @@ bottle==0.12.8
 gevent==1.0.1
 greenlet==0.4.6
 kitchen==1.2.1
-lxml==3.4.4
+lxml==4.9.1
 odfpy==0.9.6
 py==1.4.27
 pyPdf==1.13