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Severe, 6 weeks1496Projects326

1496 severe, 6 weeks · 326 projects

TensorFlowGHSA-fxqh-cfjm-fp93

Division by 0 in `Reverse`

TensorFlow

CVE-2021-29556 · Published May 21, 2021 · updated Jul 8, 2026

Low2.5
Fix: upgrade to 2.1.4 or later (4 fixed versions below)
GitHub advisory

Impact

An attacker can cause a denial of service via a FPE runtime error in tf.raw_ops.Reverse:

```python

import tensorflow as tf

tensor_input = tf.constant([], shape=[0, 1, 1], dtype=tf.int32)

dims = tf.constant([False, True, False], shape=[3], dtype=tf.bool)

tf.raw_ops.Reverse(tensor=tensor_input, dims=dims)

`

This is because the [implementation](https://github.com/tensorflow/tensorflow/blob/36229ea9e9451dac14a8b1f4711c435a1d84a594/tensorflow/core/kernels/reverse_op.cc#L75-L76) performs a division based on the first dimension of the tensor argument:

```cc

const int64 N = input.dim_size(0);

const int64 cost_per_unit = input.NumElements() / N;

`

Since this is controlled by the user, an attacker can trigger a denial of service.

Patches

We have patched the issue in GitHub commit [4071d8e2f6c45c1955a811fee757ca2adbe462c1](https://github.com/tensorflow/tensorflow/commit/4071d8e2f6c45c1955a811fee757ca2adbe462c1).

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.

###...

Affected versions

PackageAffectedFixed in
tensorflow
PyPI
< 2.1.42.1.4
>= 2.2.0, < 2.2.32.2.3
>= 2.3.0, < 2.3.32.3.3
>= 2.4.0, < 2.4.22.4.2
Details and references

### Impact An attacker can cause a denial of service via a FPE runtime error in `tf.raw_ops.Reverse`: ```python import tensorflow as tf tensor_input = tf.constant([], shape=[0, 1, 1], dtype=tf.int32) dims = tf.constant([False, True, False], shape=[3], dtype=tf.bool) tf.raw_ops.Reverse(tensor=tensor_input, dims=dims) ``` This is because the [implementation](https://github.com/tensorflow/tensorflow/blob/36229ea9e9451dac14a8b1f4711c435a1d84a594/tensorflow/core/kernels/reverse_op.cc#L75-L76) performs a division based on the first dimension of the tensor argument: ```cc const int64 N = input.dim_size(0); const int64 cost_per_unit = input.NumElements() / N; ``` Since this is controlled by the user, an attacker can trigger a denial of service. ### Patches We have patched the issue in GitHub commit [4071d8e2f6c45c1955a811fee757ca2adbe462c1](https://github.com/tensorflow/tensorflow/commit/4071d8e2f6c45c1955a811fee757ca2adbe462c1). 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 Ying Wang and Yakun Zhang of Baidu X-Team.

CVSS 3.1
CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:N/I:N/A:L
Severity from
GitHub (reviewed advisory)
Weakness
CWE-369
Also known as
BIT-tensorflow-2021-29556, CVE-2021-29556, PYSEC-2021-193, PYSEC-2021-484, PYSEC-2021-682

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