CVE-2021-37643: TensorFlow MatrixDiagPartOp Padding Value Null Pointer Dereference
Summary
CVE-2021-37643: TensorFlow is an end-to-end open source platform for machine learning. Affects tensorflow across 3 version ranges.
>= 2.3.0, < 2.3.4
>= 2.4.0, < 2.4.3
< 482da92095c4d48f8784b1f00dda4f81c28d2988
Fixed in 2.3.4 or 2.4.3, depending on the release line you run. How to fix ↓
Also tracked for
- tensorflow · Bitnami
- tensorflow-cpu · PyPI
- tensorflow-gpu · PyPI
The same CVE-2021-37643 is tracked separately for each ecosystem and vendor. Its fix information is the same; the package and affected versions differ.
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Background
TensorFlow is an end-to-end open source platform for machine learning. It provides a comprehensive set of tools, libraries, and resources for building and deploying machine learning models. TensorFlow is widely used in various domains, including research, industry, and academia. It offers support for both deep learning and traditional machine learning algorithms, making it a popular choice among developers and data scientists.
Vulnerability Detail
The vulnerability (CVE-2021-37643) in TensorFlow arises when a user fails to provide a valid padding value to the tf.raw_ops.MatrixDiagPartOp function. This triggers a null pointer dereference if the input is empty or produces invalid behavior by ignoring all values after the first. The issue stems from the implementation of the function, which reads the first value from a tensor buffer without checking if the tensor has any values to read from. This vulnerability can lead to crashes, unexpected behavior, or potential exploitation by malicious actors.
How To Fix
Latest published version: 2.21.0 as of 22 Oct 2026
pip install --upgrade "tensorflow==2.21.0"
Upgrading to it may include breaking changes; the versions below are the minimum fixed release for this vulnerability.
If you can't move to the latest
The minimum fixed version depends on the release line you run.
-
>= 2.3.0, < 2.3.42.3.4pip install --upgrade "tensorflow==2.3.4" -
>= 2.4.0, < 2.4.32.4.3pip install --upgrade "tensorflow==2.4.3"
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Workaround
As a workaround, users can ensure that a valid padding value is provided when using the tf.raw_ops.MatrixDiagPartOp function. This can be achieved by checking the input tensor for empty values before passing it to the function. Here is an example of how to implement this workaround in Python:
import tensorflow as tf
def safe_matrix_diag_part_op(input_tensor, padding_value):
if tf.size(input_tensor) > 0:
return tf.raw_ops.MatrixDiagPartOp(input=input_tensor, padding_value=padding_value)
else:
return tf.constant([], dtype=tf.float32)
Conclusion
In conclusion, the vulnerability (CVE-2021-37643) in TensorFlow's tf.raw_ops.MatrixDiagPartOp function can result in null pointer dereference or invalid behavior if a valid padding value is not provided. Users should update their TensorFlow installation to the patched versions (2.6.0, 2.5.1, 2.4.3, or 2.3.4) to mitigate the risks associated with this vulnerability. It is important to stay updated with the latest security patches and follow best practices to ensure the security and stability of machine learning applications.
See every vulnerability recorded for tensorflow →
FAQ
TensorFlow is an open source platform for machine learning that provides a comprehensive set of tools and resources for building and deploying machine learning models.
This vulnerability can lead to crashes, unexpected behavior, or potential exploitation by malicious actors. It is important to update TensorFlow to the patched versions to mitigate these risks.
To fix this vulnerability, update your TensorFlow installation to version 2.6.0 or later. Alternatively, you can also update to versions 2.5.1, 2.4.3, or 2.3.4, which have also been patched.
Yes, as a workaround, you can ensure that a valid padding value is provided when using the tf.raw_ops.MatrixDiagPartOp function. Check the input tensor for empty values before passing it to the function.
You can find more information about this vulnerability in the official TensorFlow documentation, release notes, and the GitHub commit 482da92095c4d48f8784b1f00dda4f81c28d2988.
References
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