diff --git a/performance_tests/WMTS/requirements.txt b/performance_tests/WMTS/requirements.txt
index 24e433f..5b583f7 100644
--- a/performance_tests/WMTS/requirements.txt
+++ b/performance_tests/WMTS/requirements.txt
@@ -1,2 +1,2 @@
-lxml==4.2.1
+lxml==4.9.1