CVE-2019-16778

In TensorFlow before 1.15, a heap buffer overflow in UnsortedSegmentSum can be produced when the Index template argument is int32. In this case data_size and num_segments fields are truncated from int64 to int32 and can produce negative numbers, resulting in accessing out of bounds heap memory. This is unlikely to be exploitable and was detected and fixed internally in TensorFlow 1.15 and 2.0.

### Impact A heap buffer overflow in `UnsortedSegmentSum` can be produced when the `Index` template argument is `int32`. In this case `data_size` and `num_segments` fields are truncated from `int64` to `int32` and can produce negative numbers, resulting in accessing out of bounds heap memory. This is unlikely to be exploitable and was detected and fixed internally. We are making the security advisory only to notify users that it is better to update to TensorFlow 1.15 or 2.0 or later as these versions already have this fixed. ### Patches Patched by db4f9717c41bccc3ce10099ab61996b246099892 and released in all official releases after 1.15 and 2.0. ### For more information Please consult [`SECURITY.md`](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.

En TensorFlow versiones anteriores a 1.15, un desbordamiento de búfer de la pila puede ser producido en la función UnsortedSegmentSum cuando el argumento de la plantilla Index es int32. En este caso, los campos data_size y num_segments son truncados de int64 hasta int32 y pueden producir números negativos, resultando en el acceso a la memoria de la pila fuera de los límites. Es poco probable que sea explotable y se detectó y reparó internamente en TensorFlow versiones 1.15 y 2.0.