diff --git a/prepro/requirements.txt b/prepro/requirements.txt
old mode 100755
new mode 100644
index adc1d46..bee74b5
--- a/prepro/requirements.txt
+++ b/prepro/requirements.txt
@@ -69,7 +69,7 @@ python-dateutil==2.7.5
 python-debian==0.1.32
 pytz==2018.3
 pyxdg==0.25
-PyYAML==3.12
+PyYAML==5.4
 reportlab==3.4.0
 requests==2.20.0
 requests-unixsocket==0.1.5