diff --git a/requirements.txt b/requirements.txt
index 8971d5f..73e7746 100644
--- a/requirements.txt
+++ b/requirements.txt
@@ -4,3 +4,4 @@ coolname>=1.1.0
 tabulate>=0.8.3
 tensorboardX>=1.4
 
+protobuf>=3.18.3 # not directly required, pinned by Snyk to avoid a vulnerability