diff --git a/lower-constraints.txt b/lower-constraints.txt
index bddc7c4d..1f4bc091 100644
--- a/lower-constraints.txt
+++ b/lower-constraints.txt
@@ -58,7 +58,7 @@ python-editor==1.0.3
 python-mimeparse==1.6.0
 python-subunit==1.0.0
 pytz==2013.6
-PyYAML==3.12
+PyYAML==5.3.1
 redis==2.10.0
 requests==2.14.2
 requestsexceptions==1.2.0