diff --git a/requirements.txt b/requirements.txt
index 8bdbefd..2f1eddf 100644
--- a/requirements.txt
+++ b/requirements.txt
@@ -25,7 +25,7 @@ Jinja2==2.10.1
 MarkupSafe==1.1.1
 msgpack==0.6.1
 # pkg-resources==0.0.0
-protobuf==3.9.1
+protobuf==3.18.3
 pyasn1==0.4.6
 pyasn1-modules==0.2.6
 pytz==2019.2