diff --git a/tensorflow/lite/micro/kernels/circular_buffer_common.cc b/tensorflow/lite/micro/kernels/circular_buffer_common.cc
index bf45c06f61c..461d3c92955 100644
--- a/tensorflow/lite/micro/kernels/circular_buffer_common.cc
+++ b/tensorflow/lite/micro/kernels/circular_buffer_common.cc
@@ -49,6 +49,10 @@ TfLiteStatus CircularBufferPrepare(TfLiteContext* context, TfLiteNode* node) {
 
   TF_LITE_ENSURE(context, input != nullptr);
   TF_LITE_ENSURE(context, output != nullptr);
+  // The kernel indexes dims->data[0..3] below; ensure both tensors are rank-4
+  // before any access to avoid an out-of-bounds read on malformed models.
+  TF_LITE_ENSURE_EQ(context, NumDimensions(input), 4);
+  TF_LITE_ENSURE_EQ(context, NumDimensions(output), 4);
   TF_LITE_ENSURE_EQ(context, input->dims->data[0], output->dims->data[0]);
   TF_LITE_ENSURE_EQ(context, 1, input->dims->data[1]);
   TF_LITE_ENSURE_EQ(context, input->dims->data[2], output->dims->data[2]);