Heap OOB read in TFLite
### Impact
A specially crafted TFLite model could trigger an OOB read on heap in the TFLite implementation of `Split_V`
https://github.com/tensorflow/tensorflow/blob/c59c37e7b2d563967da813fa50fe20b21f4da683/tensorflow/lite/kernels/split_v.cc#L99:
```cc
const int input_size = SizeOfDimension(input, axis_value);
```
If `axis_value` is not a value between 0 and `NumDimensions(input)`, then the `SizeOfDimension` function
https://github.com/tensorflow/tensorflow/blob/102b211d892f3abc14f845a72047809b39cc65ab/tensorflow/lite/kernels/kernel_util.h#L148-L150 will access data outside the bounds of the tensor shape array:
```cc
inline int SizeOfDimension(const TfLiteTensor* t, int dim) {
return t->dims->data[dim];
}
```
### Patches
We have patched the issue in GitHub commit ae2daeb45abfe2c6dda539cf8d0d6f653d3ef412
https://github.com/tensorflow/tensorflow/commit/ae2daeb45abfe2c6dda539cf8d0d6f653d3ef412.
The fix will be included in TensorFlow 2.5.0. We will also cherrypick this commit on TensorFlow 2.4.2, TensorFlow 2.3.3, TensorFlow 2.2.3 and TensorFlow 2.1.4, 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.