TensorFlowGHSA-fcwc-p4fc-c5cc

Null pointer dereference in `MatrixDiagPartOp`

CVE-2021-37643 · Published Aug 25, 2021 · updated Jul 8, 2026

High7.7

Fix: upgrade to 2.3.4 or later (3 fixed versions below)

Impact

If a user does not provide a valid padding value to tf.raw_ops.MatrixDiagPartOp, then the code triggers a null pointer dereference (if input is empty) or produces invalid behavior, ignoring all values after the first:

```python

import tensorflow as tf

tf.raw_ops.MatrixDiagPartV2(

input=tf.ones(2,dtype=tf.int32),

k=tf.ones(2,dtype=tf.int32),

padding_value=[])

Although this example is given for MatrixDiagPartV2, all versions of the operation are affected.

The [implementation](https://github.com/tensorflow/tensorflow/blob/8d72537c6abf5a44103b57b9c2e22c14f5f49698/tensorflow/core/kernels/linalg/matrix_diag_op.cc#L89) reads the first value from a tensor buffer without first checking that the tensor has values to read from.

Patches

We have patched the issue in GitHub commit [482da92095c4d48f8784b1f00dda4f81c28d2988](https://github.com/tensorflow/tensorflow/commit/482da92095c4d48f8784b1f00dda4f81c28d2988).

The fix will be included in TensorFlow 2.6.0. We will also cherrypick this commit on TensorFlow 2.5.1, TensorFlow 2.4.3, and TensorFlow 2.3.4, 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...

Affected versions

Package	Affected	Fixed in
tensorflow PyPI	< 2.3.4	2.3.4
	>= 2.4.0, < 2.4.3	2.4.3
	>= 2.5.0, < 2.5.1	2.5.1

Details and references

### Impact If a user does not provide a valid padding value to `tf.raw_ops.MatrixDiagPartOp`, then the code triggers a null pointer dereference (if input is empty) or produces invalid behavior, ignoring all values after the first: ```python import tensorflow as tf tf.raw_ops.MatrixDiagPartV2( input=tf.ones(2,dtype=tf.int32), k=tf.ones(2,dtype=tf.int32), padding_value=[]) ``` Although this example is given for `MatrixDiagPartV2`, all versions of the operation are affected. The [implementation](https://github.com/tensorflow/tensorflow/blob/8d72537c6abf5a44103b57b9c2e22c14f5f49698/tensorflow/core/kernels/linalg/matrix_diag_op.cc#L89) reads the first value from a tensor buffer without first checking that the tensor has values to read from. ### Patches We have patched the issue in GitHub commit [482da92095c4d48f8784b1f00dda4f81c28d2988](https://github.com/tensorflow/tensorflow/commit/482da92095c4d48f8784b1f00dda4f81c28d2988). The fix will be included in TensorFlow 2.6.0. We will also cherrypick this commit on TensorFlow 2.5.1, TensorFlow 2.4.3, and TensorFlow 2.3.4, 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.

CVSS 3.1: CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:H
Severity from: GitHub (reviewed advisory)
Weakness: CWE-476
Also known as: BIT-tensorflow-2021-37643, CVE-2021-37643, PYSEC-2021-265, PYSEC-2021-556, PYSEC-2021-754

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