diff --git a/unity/requirements.txt b/unity/requirements.txt
old mode 100755
new mode 100644
index ed3ebf8..5a820fe
--- a/unity/requirements.txt
+++ b/unity/requirements.txt
@@ -6,5 +6,5 @@ jupyter
 pytest>=3.2.2
 docopt
 pyyaml
-protobuf==3.5.2
+protobuf==3.18.3
 grpcio==1.11.0