TensorFlow vulnerable to `CHECK` fail in `tf.sparse.cross`

Impact

If tf.sparse.cross receives an input separator that is not a scalar, it gives a CHECK fail that can be used to trigger a denial of service attack.

```python

import tensorflow as tf

tf.sparse.cross(inputs=[],name='a',separator=tf.constant(['a', 'b'],dtype=tf.string))

`

Patches

We have patched the issue in GitHub commit [83dcb4dbfa094e33db084e97c4d0531a559e0ebf](https://github.com/tensorflow/tensorflow/commit/83dcb4dbfa094e33db084e97c4d0531a559e0ebf).

The fix will be included in TensorFlow 2.10.0. We will also cherrypick this commit on TensorFlow 2.9.1, TensorFlow 2.8.1, and TensorFlow 2.7.2, as these are also affected and still in supported range.

For more information

Please consult [our security guide](https://github.com/tensorflow/tensorflow/blob/master/SECURITY.md) for more information regarding the security model and how to contact us with issues and questions.

Attribution

This vulnerability has been reported by Kang Hong Jin.