diff --git a/hbp_nrp_cle/requirements.txt b/hbp_nrp_cle/requirements.txt
old mode 100755
new mode 100644
index b8d07f5..2067e2c
--- a/hbp_nrp_cle/requirements.txt
+++ b/hbp_nrp_cle/requirements.txt
@@ -2,7 +2,7 @@
 cython==0.23.4
 numpy==1.16.5
 scipy==0.17.1
-lxml==3.4.0
+lxml==4.9.1
 h5py==2.6.0
 lazyarray==0.3.2
 neo==0.5.2