CVE-2021-37668Public exploit

Service crash via zero dimension in UnravelIndex

Published Aug 12, 2021 · Updated Aug 4, 2024

Divide-by-zero in Google TensorFlow before 2.3.4, 2.4.0 through 2.4.2, and 2.5.0 allows local users to crash model-serving processes. The UnravelIndexOp kernel multiplies dims and divides indices by that product without rejecting a zero dimension, producing a floating-point exception. Reachability requires an application to pass attacker-controlled dimensions to the operation; the bounded impact is a crash of the serving process.

CVSS severity5.5
Medium
EPSS probability0.15%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Divide-by-zero in Google TensorFlow before 2.3.4, 2.4.0 through 2.4.2, and 2.5.0 allows local users to crash model-serving processes. The UnravelIndexOp kernel multiplies dims and divides indices by that product without rejecting a zero dimension, producing a floating-point exception. Reachability requires an application to pass attacker-controlled dimensions to the operation; the bounded impact is a crash of the serving process.

The record

CVE
CVE-2021-37668
Published
Aug 12, 2021
Updated
Aug 4, 2024
Vendor
Google
Product
TensorFlow
Classifications
CWE-369, T1499.004
Attack vector
local
Privileges
authenticated

Timeline

How it unfolded

  1. Aug 12, 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=< 2.3.4
  2. Affected versionversion=>= 2.4.0, < 2.4.3
  3. Affected versionversion=>= 2.5.0, < 2.5.1

What conditions does exploitation require?

Attack vectorlocal
Required privilegesauthenticated

What is affected?

Google · TensorFlowversion=< 2.3.4; version=>= 2.4.0, < 2.4.3; version=>= 2.5.0, < 2.5.1

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 NVDAV: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.

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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
T1499.004Endpoint Denial of Service: Application 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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