CVE-2021-37679Public exploit

Heap disclosure via unchecked RaggedTensor inner shapes

Published Aug 12, 2021 · Updated Aug 4, 2024

Out-of-bounds reads in Google TensorFlow before 2.3.4, 2.4.0 through 2.4.2, and 2.5.0 allow local users to disclose heap data. The Variant-to-RaggedTensor conversion fails to verify that all inner tensor shapes match, so nested tf.map_fn fills an incorrectly shaped output with uninitialized heap contents. Execution requires local low-privileged code to supply a RaggedTensor to nested tf.map_fn without a function signature; crafted shapes disclose heap data or truncate output data.

CVSS severity8.4
High
EPSS probability0.18%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Out-of-bounds reads in Google TensorFlow before 2.3.4, 2.4.0 through 2.4.2, and 2.5.0 allow local users to disclose heap data. The Variant-to-RaggedTensor conversion fails to verify that all inner tensor shapes match, so nested tf.map_fn fills an incorrectly shaped output with uninitialized heap contents. Execution requires local low-privileged code to supply a RaggedTensor to nested tf.map_fn without a function signature; crafted shapes disclose heap data or truncate output data.

The record

CVE
CVE-2021-37679
Published
Aug 12, 2021
Updated
Aug 4, 2024
Vendor
Google
Product
TensorFlow
Classifications
CWE-681, CWE-125
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

7.8GitLab Advisory DatabaseCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
8.4GitHub Advisory DatabaseCVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:N/SC:N/SI:N/SA:N

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-681Incorrect Conversion between Numeric Types
CWE-125Out-of-bounds Read

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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