CVE-2021-29575: TensorFlow ReverseSequence Stack Overflow and Denial of Service
Summary
CVE-2021-29575: TensorFlow is an end-to-end open source platform for machine learning. Affects tensorflow across 5 version ranges.
>= 2.2.0, < 2.2.3
< 2.2.0rc0
>= 2.3.0, < 2.3.3
>= 2.4.0, < 2.4.2
< ecf768cbe50cedc0a45ce1ee223146a3d3d26d23
Fixed in 4 releases; the minimum fixed version depends on the release line you run. How to fix ↓
Also tracked for
- tensorflow · Bitnami
- tensorflow-cpu · PyPI
- tensorflow-gpu · PyPI
The same CVE-2021-29575 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 for building and deploying machine learning models. TensorFlow includes various operations and functions to manipulate and process data efficiently. One such operation is tf.raw_ops.ReverseSequence, which is used to reverse the elements of a sequence along a specified dimension. This operation is vulnerable to a stack overflow and/or denial of service attack due to improper validation of input arguments.
Vulnerability Detail
The vulnerability in TensorFlow's tf.raw_ops.ReverseSequence operation arises from the lack of proper validation of the seq_dim and batch_dim arguments. Negative values for seq_dim can lead to a stack overflow, while invalid values for batch_dim can result in a CHECK failure. The impact of this vulnerability depends on the version of Eigen code used to implement the operation. The vulnerability allows an attacker to cause a denial of service by crashing the TensorFlow process or potentially executing arbitrary code.
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.
-
< 2.2.0rc02.2.0rc0pip install --upgrade "tensorflow==2.2.0rc0" -
>= 2.2.0, < 2.2.32.2.3pip install --upgrade "tensorflow==2.2.3" -
>= 2.3.0, < 2.3.32.3.3pip install --upgrade "tensorflow==2.3.3" -
>= 2.4.0, < 2.4.22.4.2pip install --upgrade "tensorflow==2.4.2"
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Workaround
As a temporary workaround, you can avoid using the tf.raw_ops.ReverseSequence operation or ensure that the input arguments (seq_dim and batch_dim) are valid and within the expected range. Additionally, you can monitor the TensorFlow process for abnormal behavior or crashes as indicators of a potential attack.
Conclusion
The vulnerability in TensorFlow's tf.raw_ops.ReverseSequence operation can lead to a stack overflow and denial of service. It is crucial to update your TensorFlow installation to the patched version or apply the backported fix to ensure the security and stability of your machine learning applications. For further support on vulnerability remediation, please contact DevNack.com.
See every vulnerability recorded for tensorflow →
FAQ
TensorFlow is an open source platform for machine learning that provides a comprehensive ecosystem for building and deploying machine learning models.
tf.raw_ops.ReverseSequence is used to reverse the elements of a sequence along a specified dimension in TensorFlow.
This vulnerability can lead to a denial of service by crashing the TensorFlow process or potentially executing arbitrary code.
The vulnerability affects TensorFlow versions 2.1.4, 2.2.3, 2.3.3, 2.4.2, and prior versions.
To fix this vulnerability, upgrade your TensorFlow installation to version 2.5.0 or apply the backported fix for versions 2.4.2, 2.3.3, 2.2.3, and 2.1.4.
References
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