diff --git a/azure/cpu-memory/pyaes/requirements.txt b/azure/cpu-memory/pyaes/requirements.txt
index 65bf1b9..27438c9 100644
--- a/azure/cpu-memory/pyaes/requirements.txt
+++ b/azure/cpu-memory/pyaes/requirements.txt
@@ -3,7 +3,7 @@ azure-functions==1.0.0b3
 azure-functions-worker==1.0.0b3
 grpcio==1.14.2
 grpcio-tools==1.14.2
-protobuf==3.15.0
+protobuf==3.18.3
 six==1.12.0
 
 pyaes
\ No newline at end of file