Heap OOB read in `tf.raw_ops.SparseCountSparseOutput`

Impact

The [shape inference functions for SparseCountSparseOutput](https://github.com/tensorflow/tensorflow/blob/e0b6e58c328059829c3eb968136f17aa72b6c876/tensorflow/core/ops/count_ops.cc#L43-L50) can trigger a read outside of bounds of heap allocated array:

```python

import tensorflow as tf

@tf.function

def func():

return tf.raw_ops.SparseCountSparseOutput(

indices=[1],

values=[[1]],

dense_shape=[10],

weights=[],

binary_output= True)

func()

`

The function fails to check that the first input (i.e., indices) has rank 2:

```cc

auto rank = c->Dim(c->input(0), 1);

`

Patches

We have patched the issue in GitHub commit [701cfaca222a82afbeeb17496bd718baa65a67d2](https://github.com/tensorflow/tensorflow/commit/701cfaca222a82afbeeb17496bd718baa65a67d2).

The fix will be included in TensorFlow 2.7.0. We will also cherrypick this commit on TensorFlow 2.6.1, TensorFlow 2.5.2, and TensorFlow 2.4.4, 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 members of the Aivul Team from Qihoo 360.