CVE-2021-41207Public exploit

Service interruption via unchecked ParallelConcat dimensions

Published Nov 5, 2021 · Updated Aug 4, 2024

Division by zero in Google TensorFlow allows local users to interrupt affected processes through a zero-sized ParallelConcat input. The ParallelConcatUpdate kernel fails to reject a rank-zero value or a value whose first dimension does not cover loc, allowing invalid dimensions to reach later computation. Triggering the condition requires local ability to execute a crafted TensorFlow graph, and the bounded consequence is termination of that process without reported data disclosure or modification.

CVSS severity5.5
Medium
EPSS probability0.14%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Division by zero in Google TensorFlow allows local users to interrupt affected processes through a zero-sized ParallelConcat input. The ParallelConcatUpdate kernel fails to reject a rank-zero value or a value whose first dimension does not cover loc, allowing invalid dimensions to reach later computation. Triggering the condition requires local ability to execute a crafted TensorFlow graph, and the bounded consequence is termination of that process without reported data disclosure or modification.

The record

CVE
CVE-2021-41207
Published
Nov 5, 2021
Updated
Aug 4, 2024
Vendor
Google
Product
TensorFlow
Classifications
CWE-369, T1499.004
Attack vector
local
Privileges
authenticated

Timeline

How it unfolded

  1. Nov 5, 2021CVE publishedPublication date reported by the CVE source.
  2. Aug 4, 2024Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=< 2.4.4
  2. Affected versionversion=>= 2.5.0, < 2.5.2
  3. Affected versionversion=>= 2.6.0, < 2.6.1

What conditions does exploitation require?

Attack vectorlocal
Required privilegesauthenticated

What is affected?

Google · TensorFlowversion=< 2.4.4; version=>= 2.5.0, < 2.5.2; version=>= 2.6.0, < 2.6.1

Published CVSS scores

5.5GitHub, Inc.CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
2.1NIST National Vulnerability DatabaseAV:L/AC:L/Au:N/C:N/I:N/A:P

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

Daily unique IPsNo honeypot observations are available for this CVE in the selected window.

No observations available

Sep 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectorlocal
Privilegesauthenticated
Known exploitationUnconfirmed
Public exploitPublished

Weakness, pattern, technique

CWE-369Divide By Zero
T1499.004Application or System Exploitation

Public exploit references

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

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Your stack

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