diff --git a/explainer/requirements.txt b/explainer/requirements.txt
index 87a0f3e..e835ef7 100644
--- a/explainer/requirements.txt
+++ b/explainer/requirements.txt
@@ -61,7 +61,7 @@ pyparsing==2.4.0
 pyrsistent==0.15.3
 python-dateutil==2.8.0
 pytz==2019.1
-PyYAML==5.1.1
+PyYAML==5.4
 pyzmq==18.0.2
 qtconsole==4.5.1
 rope==0.14.0