diff --git a/requirements.txt b/requirements.txt
index 119dbd6..be4ad57 100644
--- a/requirements.txt
+++ b/requirements.txt
@@ -26,7 +26,7 @@ pyparsing==2.4.0
 pytest==4.6.3
 pytest-cov==2.7.1
 python-dateutil==2.8.0
-PyYAML==5.1.1
+PyYAML==5.4
 requests==2.22.0
 s3transfer==0.2.1
 scipy==1.3.0