diff --git a/requirements.txt b/requirements.txt
index 79d6f67..1274147 100644
--- a/requirements.txt
+++ b/requirements.txt
@@ -17,7 +17,7 @@ pygments
 pyserial==3.4
 pytest==6.0.1
 pytest-mock==3.3.1
-PyYAML==5.3.1
+PyYAML==5.4
 RPi.GPIO==0.7.0
 RPIO==0.10.0
 soupsieve==1.9.6