diff --git a/requirements.txt b/requirements.txt
index 444bfae..72a9375 100644
--- a/requirements.txt
+++ b/requirements.txt
@@ -20,7 +20,7 @@ Markdown==2.6.11
 matplotlib==2.2.2
 numba==0.37.0
 numpy==1.14.2
-protobuf==3.5.2.post1
+protobuf==3.18.3
 pycparser==2.18
 pydot==1.2.4
 pyparsing==2.2.0