diff --git a/components/kubeflow/dnntrainer/requirements.txt b/components/kubeflow/dnntrainer/requirements.txt
index f8693cbf896..bc0bc21ae55 100644
--- a/components/kubeflow/dnntrainer/requirements.txt
+++ b/components/kubeflow/dnntrainer/requirements.txt
@@ -2,3 +2,4 @@ pyyaml==3.12
 six==1.11.0
 tensorflow-transform==0.23.0
 tensorflow-model-analysis==0.23.0
+tornado>=6.4.2 # not directly required, pinned by Snyk to avoid a vulnerability