diff --git a/requirements.txt b/requirements.txt
index 581d94a..4f73a83 100644
--- a/requirements.txt
+++ b/requirements.txt
@@ -1,6 +1,6 @@
 grpcio-tools>=1.9.0,<=1.10.0
 grpcio>=1.9.0,<=1.10.0
-PyYAML==5.3
+PyYAML==5.3.1
 pytest==5.2.2
 mock>=2.0.0
 pyqrllib>=0.9.0,<0.10.0