CVE-2021-29544: Denial of Service in TensorFlow
Summary
CVE-2021-29544: TensorFlow is an end-to-end open source platform for machine learning. Affects tensorflow-cpu across 5 version ranges.
>= 2.2.0, < 2.3.0rc0
< 2.2.0rc0
>= 2.3.0, < 2.3.4
>= 2.4.0, < 2.4.3
< 20431e9044cf2ad3c0323c34888b192f3289af6b
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-2021-29544 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 is widely used in various domains, including research, industry, and academia. It offers support for both CPU and GPU computations, enabling efficient training and inference on a wide range of hardware configurations. However, a vulnerability has been discovered in TensorFlow that can lead to a denial of service attack.
Vulnerability Detail
The vulnerability (CVE-2021-29544) in TensorFlow is triggered by a CHECK-fail in the tf.raw_ops.QuantizeAndDequantizeV4Grad function. The implementation of this function does not properly validate the rank of the input tensors, allowing an attacker to pass tensors with an incorrect rank. This leads to a CHECK failure in the vec<T> method, resulting in a denial of service. The issue has been identified in the codebase and a fix will be included in TensorFlow 2.5.0. The affected versions include TensorFlow 2.2.0rc0, 2.2.0, 2.3.0rc0, 2.3.0, 2.3.4, 2.4.0, and 2.4.3.
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.
-
< 2.2.0rc02.2.0rc0pip install --upgrade "tensorflow-cpu==2.2.0rc0" -
>= 2.2.0, < 2.3.0rc02.3.0rc0pip install --upgrade "tensorflow-cpu==2.3.0rc0" -
>= 2.3.0, < 2.3.42.3.4pip install --upgrade "tensorflow-cpu==2.3.4" -
>= 2.4.0, < 2.4.32.4.3pip install --upgrade "tensorflow-cpu==2.4.3"
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Workaround
There is no specific workaround mentioned for this vulnerability. However, users can mitigate the risk by following the recommended fix and updating to the patched versions of TensorFlow.
Conclusion
The vulnerability in TensorFlow (CVE-2021-29544) can lead to a denial of service attack. It is crucial for users of affected versions to update to the patched versions or apply the provided patch to ensure the security and stability of their machine learning workflows. For further support on 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 tools and libraries for developing and deploying machine learning models.
The vulnerability can be exploited by an attacker to trigger a denial of service attack, potentially disrupting machine learning workflows and impacting system availability.
The vulnerability affects TensorFlow versions 2.2.0rc0, 2.2.0, 2.3.0rc0, 2.3.0, 2.3.4, 2.4.0, and 2.4.3.
To fix the vulnerability, it is recommended to update TensorFlow to version 2.5.0 once it is released. Alternatively, users can upgrade to TensorFlow 2.4.2 or apply the provided patch manually.
There is no specific workaround mentioned for this vulnerability. However, users can mitigate the risk by following the recommended fix and updating to the patched versions of TensorFlow.
References
Related vulnerabilities
Recent vulnerabilities recorded for tensorflow-cpu.