CVE-2021-29601: TensorFlow Integer Overflow in TFLite Concatenation

tensorflow-cpu Updated 02 Oct 2025

Summary

14/05/2021
Yes i
Unrated
Not published

CVE-2021-29601: 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 < 4253f96a58486ffe84b61c0415bb234a4632ee73

Fixed in 4 releases; the minimum fixed version depends on the release line you run. How to fix ↓

Also tracked for

The same CVE-2021-29601 is tracked separately for each ecosystem and vendor. Its fix information is the same; the package and affected versions differ.

Free scan

Check if this vulnerability affects your application

Upload a manifest or SBOM and we'll show whether you're affected, plus every other risky package in the same scan.

Check my app free

No signup required · Results in about 60 seconds

Sponsored Devnack Penetration testing for web, API and mobile Manual testing by engineers who build software, not an auditor's checklist. Trusted by teams at Swift and Google Talk to Devnack

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. The TensorFlow Lite (TFLite) implementation is specifically designed for running machine learning models on resource-constrained devices. TFLite uses int to represent tensor dimensions, while TensorFlow (TF) uses int64. This vulnerability arises from an integer overflow issue in the TFLite implementation of concatenation, where the dimensions of one of the concatenation inputs can overflow the values of int. This vulnerability affects the TensorFlow package, specifically the tensorflow-cpu package on PyPI.

Vulnerability Detail

The vulnerability in TensorFlow allows an attacker to craft a malicious model that triggers an integer overflow when converted to TFLite format. By manipulating the dimensions of one of the concatenation inputs, the attacker can cause an integer overflow in the TFLite implementation. This can lead to various consequences, such as memory corruption, crashes, or even potential remote code execution. The vulnerability affects versions of TensorFlow from 0 to 2.4.2, as well as versions 2.1.4, 2.2.3, and 2.3.3. The issue has been identified and fixed in TensorFlow 2.5.0.

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.

  • < 2.1.4 2.1.4
    pip install --upgrade "tensorflow-cpu==2.1.4"
  • >= 2.2.0, < 2.2.3 2.2.3
    pip install --upgrade "tensorflow-cpu==2.2.3"
  • >= 2.3.0, < 2.3.3 2.3.3
    pip install --upgrade "tensorflow-cpu==2.3.3"
  • >= 2.4.0, < 2.4.2 2.4.2
    pip install --upgrade "tensorflow-cpu==2.4.2"

Tip — Not sure which release line you're on? Vulert can find the fix for the version you are using. Scan free →

Workaround

As a workaround, users can avoid using the TFLite implementation of concatenation and instead use the TensorFlow implementation. This can be achieved by converting the model to TensorFlow format instead of TFLite format. However, this workaround may not be feasible in all scenarios and may require modifications to the existing codebase.

Conclusion

The vulnerability in TensorFlow's TFLite implementation of concatenation can be exploited through a crafted model to trigger an integer overflow. This can result in memory corruption, crashes, or potential remote code execution. It is crucial to update to the fixed versions of TensorFlow or apply the recommended workarounds to mitigate the risk. For further assistance or support in vulnerability remediation, please contact DevNack.com.

See every vulnerability recorded for tensorflow-cpu →

Share this vulnerability

FAQ

TensorFlow is an open source platform for machine learning that provides tools and resources for developing and deploying machine learning models.

TensorFlow Lite (TFLite) is a lightweight version of TensorFlow designed for running machine learning models on resource-constrained devices.

This vulnerability can lead to memory corruption, crashes, or potential remote code execution when a malicious model triggers an integer overflow in the TFLite implementation of concatenation.

Versions of TensorFlow from 0 to 2.4.2, as well as versions 2.1.4, 2.2.3, and 2.3.3, are affected by this vulnerability.

To fix this vulnerability, it is recommended to upgrade to TensorFlow 2.5.0 or later. Alternatively, users can use the TensorFlow implementation of concatenation instead of TFLite.

Related vulnerabilities

Recent vulnerabilities recorded for tensorflow-cpu.

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.

  • < 2.1.4 2.1.4
    pip install --upgrade "tensorflow-cpu==2.1.4"
  • >= 2.2.0, < 2.2.3 2.2.3
    pip install --upgrade "tensorflow-cpu==2.2.3"
  • >= 2.3.0, < 2.3.3 2.3.3
    pip install --upgrade "tensorflow-cpu==2.3.3"
  • >= 2.4.0, < 2.4.2 2.4.2
    pip install --upgrade "tensorflow-cpu==2.4.2"

Tip — Not sure which release line you're on? Vulert can find the fix for the version you are using. Scan free →

Subscribe to Vulert on Telegram
Daily digest of new CVEs, critical and high severity, affected packages and fixes — plus a weekly roundup.
Join the channel →
Help improve this record
Report an issue or send feedback