CVE-2021-29516: TensorFlow CPU - Null Pointer Dereference in RaggedTensorToVariant
Summary
CVE-2021-29516: TensorFlow is an end-to-end open source platform for machine learning. Affects tensorflow-cpu across 5 version ranges.
< 2.1.4
>= 2.2.0, < 2.2.3
>= 2.3.0, < 2.3.3
>= 2.4.0, < 2.4.2
< b055b9c474cd376259dde8779908f9eeaf097d93
Fixed in 4 releases; the minimum fixed version depends on the release line you run. How to fix ↓
Also tracked for
- tensorflow · Bitnami
- tensorflow · PyPI
- tensorflow · PyPI
- tensorflow-gpu · PyPI
The same CVE-2021-29516 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 ecosystem of tools, libraries, and resources for developing and deploying machine learning models. TensorFlow allows users to build and train neural networks, perform data preprocessing and augmentation, and deploy models in various environments. It is widely used in both research and production settings for a wide range of machine learning tasks.
Vulnerability Detail
The vulnerability identified as CVE-2021-29516 affects the TensorFlow CPU package. Specifically, the issue arises when calling the tf.raw_ops.RaggedTensorToVariant function with arguments that specify an invalid ragged tensor. This leads to a null pointer dereference in the implementation of the RaggedTensorToVariant operation. The vulnerability occurs because the implementation does not validate that the ragged tensor argument is non-empty. As a result, when the batched_ragged tensor contains no elements, the batched_ragged.splits vector becomes null, causing a null pointer dereference when accessing batched_ragged.splits(0). The vulnerability can be exploited by an attacker to cause a denial of service or potentially execute arbitrary code in the context of the TensorFlow application.
How To Fix
Latest published version: 2.21.0 as of 22 Oct 2026
pip install --upgrade "tensorflow-cpu==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.
-
< 2.1.42.1.4pip install --upgrade "tensorflow-cpu==2.1.4" -
>= 2.2.0, < 2.2.32.2.3pip install --upgrade "tensorflow-cpu==2.2.3" -
>= 2.3.0, < 2.3.32.3.3pip install --upgrade "tensorflow-cpu==2.3.3" -
>= 2.4.0, < 2.4.22.4.2pip install --upgrade "tensorflow-cpu==2.4.2"
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Workaround
There is no specific workaround provided for this vulnerability. The recommended approach is to upgrade to a fixed version of TensorFlow.
Conclusion
The vulnerability identified as CVE-2021-29516 in TensorFlow CPU can lead to a null pointer dereference, potentially resulting in a denial of service or arbitrary code execution. It is crucial to upgrade to a fixed version of TensorFlow (2.5.0 or later) or apply the backported fix for affected versions (2.4.2, 2.3.3, 2.2.3, and 2.1.4). For further assistance or support in vulnerability remediation, please contact DevNack.com.
See every vulnerability recorded for tensorflow-cpu →
FAQ
TensorFlow is an open source platform for machine learning that provides a comprehensive set of tools and libraries for developing and deploying machine learning models.
The vulnerability can lead to a null pointer dereference in TensorFlow, potentially causing a denial of service or enabling arbitrary code execution.
The vulnerability affects TensorFlow versions 2.1.4 and later, including versions 2.4.2, 2.3.3, 2.2.3, and 2.1.4.
Yes, the vulnerability has been fixed in TensorFlow version 2.5.0. The fix has also been backported to versions 2.4.2, 2.3.3, 2.2.3, and 2.1.4.
To protect your TensorFlow installation, it is recommended to upgrade to a fixed version (2.5.0 or later) or apply the backported fix for your specific version.
References
Related vulnerabilities
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