diff --git a/requirements.txt b/requirements.txt
old mode 100755
new mode 100644
index d837d583..6b60b04b
--- a/requirements.txt
+++ b/requirements.txt
@@ -4,7 +4,7 @@ cycler==0.10.0
 Cython==0.29.19
 idna==2.9
 kiwisolver==1.2.0
-lxml==4.5.1
+lxml==4.9.1
 matplotlib==3.2.1
 numpy==1.18.4
 pandas==1.0.3