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CVE Record

CVE-2021-29527: Division by 0 in `QuantizedConv2D`

TensorFlow is an end-to-end open source platform for machine learning. An attacker can trigger a division by 0 in `tf.raw_ops.QuantizedConv2D`. This is because the implementation(https://github.com/tensorflow/tensorflow/blob/00e9a4d67d76703fa1aee33dac582acf317e0e81/tensorflow/core/kernels/quantized_conv_ops.cc#L257-L259) does a division by a quantity that is controlled by the caller. The fix will be included in TensorFlow 2.5.0. We will also cherrypick this commit on TensorFlow 2.4.2, TensorFlow 2.3.3, TensorFlow 2.2.3 and TensorFlow 2.1.4, as these are also affected and still in supported range.

LowCVSS 2.5Not KEV-listedUpdated
Glexia's TakeAutomated analysislow

Security readout for executives and security teams

Plain-English summary

CVE-2021-29527 is a low-severity TensorFlow flaw where a caller can trigger a divide-by-zero condition in QuantizedConv2D. The documented impact is limited availability loss, such as a crash or failed computation, not data theft or integrity compromise.

Executive priority

Treat as routine patch management unless affected TensorFlow workloads process untrusted local inputs or run in shared compute environments. Prioritize shared ML infrastructure where a crash could disrupt production or tenant workloads.

Technical view

TensorFlow tf.raw_ops.QuantizedConv2D divided by a caller-controlled quantity in quantized_conv_ops.cc, creating CWE-369 divide-by-zero exposure. The CVSS 3.1 score is 2.5 with local access, high attack complexity, low privileges, no user interaction, and low availability impact only.

Likely exposure

Exposure is most likely in environments running affected TensorFlow versions and allowing low-privileged local users or controlled callers to invoke QuantizedConv2D with crafted parameters. Internet-facing exposure is not established by the sources.

Exploitation context

The provided sources do not identify active exploitation, and this CVE is not marked KEV. Exploitation requires local access, low privileges, and high complexity according to the supplied CVSS vector.

Researcher notes

The issue is narrowly scoped to a divide-by-zero in QuantizedConv2D from a caller-controlled divisor. The sources name the fix commit and fixed release lines, but do not provide evidence of remote exploitation or confidentiality impact.

Mitigation direction

  • Upgrade to TensorFlow 2.5.0 or a fixed supported patch release.
  • For 2.4.x, upgrade to at least TensorFlow 2.4.2.
  • For 2.3.x, upgrade to at least TensorFlow 2.3.3.
  • For 2.2.x, upgrade to at least TensorFlow 2.2.3.
  • For 2.1.x or older supported deployments, check vendor guidance for 2.1.4.

Validation and detection

  • Inventory TensorFlow versions across notebooks, services, batch jobs, and ML build images.
  • Flag versions below 2.1.4 and affected 2.2.x, 2.3.x, and 2.4.x ranges.
  • Confirm whether QuantizedConv2D or tf.raw_ops.QuantizedConv2D is reachable in local workloads.
  • Verify upgraded environments report fixed TensorFlow versions before redeployment.
Prepared
Confidence
high
Sources
4

Generated from the cited source records. This long-tail analysis has not been individually reviewed by a named human.

Potential ATT&CK relevance

Conservative CVE-to-ATT&CK context

These mappings and lookup hints may be relevant to the vulnerability behavior, CWE, affected product, or exposure path. Glexia-inferred context is not an official MITRE, ATT&CK, CWE, or CVE Program mapping.

ATT&CK lookup starting points

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cwe · low confidence lookup

CWE-369: Exact CWE lookup

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Open ATT&CK lookup
cve · low confidence lookup

CVE-2021-29527 mapping review

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Vulnerability profileCVE Program record
Severity
Low
CVSS
2.5 (3.1)
Known Exploited
No
Published

Vector: CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:N/I:N/A:L

Official CVE source material

CNA and ADP enrichment extracted from CVE v5

These fields come from the CVE record and ADP containers, not from Glexia's Take. They preserve time-varying source decisions such as CISA SSVC, KEV status, CVSS metrics, and provider references.

1CVSS vectors
0Timeline events
0ADP providers
3Source links

CVSS vector scores

1 official score

We collect every scored CVSS vector available in the official CNA and ADP containers. When more than one version is present, the table keeps the source vectors side by side instead of collapsing them into the highest score.

ScoreVersionSeverityVectorExploitImpactSource
2.5CVSS 3.1LowCVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:N/I:N/A:L11.4Primary CVE score

Vulnerability scoring details

Base CVSS 3.1 score

2.5Low
CVSS 3.1 vector shape for CVE-2021-29527Attack VectorAttack ComplexityPrivileges RequiredUser InteractionScopeConfidentiality ImpactIntegrity ImpactAvailability Impact

Vector: CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:N/I:N/A:L

Attack Vector
NetworkAdjacentLocalPhysical
Attack Complexity
LowHigh
Privileges Required
NoneLowHigh
User Interaction
NoneRequired
Scope
ChangedUnchanged
Confidentiality Impact
HighLowNone
Integrity Impact
HighLowNone
Availability Impact
HighLowNone
Affected products

Products and packages named in the record

VendorProductVersion / packageStatus
tensorflowtensorflow< 2.1.4, >= 2.2.0, < 2.2.3, >= 2.3.0, < 2.3.3, >= 2.4.0, < 2.4.2Listed
Weakness

CWE details

CWE links open Glexia weakness intelligence pages with official CWE context, developer remediation guidance, and related CVE mappings.

CWE-369 · source CWE mapping

Divide By Zero

Divide By Zero represents a recurring weakness pattern that can create exploitable paths when design, validation, or implementation controls are missing.