diff --git a/web-app-flask/requirements.txt b/web-app-flask/requirements.txt
index cfe1523..7d0e1f4 100644
--- a/web-app-flask/requirements.txt
+++ b/web-app-flask/requirements.txt
@@ -20,7 +20,7 @@ Jinja2==2.11.2
 MarkupSafe==1.1.1
 oauth2client==4.1.3
 oauthlib==3.1.0
-protobuf==3.11.3
+protobuf==3.18.3
 pyasn1==0.4.8
 pyasn1-modules==0.2.8
 pytz==2020.1