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NVD / CVE Program· CNA GitHub_M

CVE-2021-37640: Integer division by 0 in sparse reshaping in TensorFlow

Noroxi assessment

Priority: Monitor (action score 22/100)

  • The sources we track (CISA KEV, Exploit-DB, Metasploit, Nuclei, GitHub) show no public exploit code or exploitation in the wild.
  • Probability of exploitation in the next 30 days: 0.15% (FIRST EPSS).
  • Someone with local access to the system can trigger it. A low-privileged account is enough. No user action is required. No special conditions are required; it is repeatable.
  • Fixed version: bazel-skylib1.0.3 (openSUSE:Leap 15.3) 1.0.3-bp153.2.1; bazel3.7 (openSUSE:Leap 15.3) 3.7.2-bp153.4.1; tensorflow2 (openSUSE:Leap 15.3) 2.6.0-bp153.2.3.1.

Low priority for now. Upgrade to bazel-skylib1.0.3 (openSUSE:Leap 15.3) 1.0.3-bp153.2.1; bazel3.7 (openSUSE:Leap 15.3) 3.7.2-bp153.4.1; tensorflow2 (openSUSE:Leap 15.3) 2.6.0-bp153.2.3.1 or later.

Generated automatically from the record's data: CVSS (NVD and CNA), CISA KEV and SSVC, FIRST EPSS, exploit sources, fixed versions. How we calculate it

Primary sources: NVD · CVE.org · FIRST EPSS

TensorFlow is an end-to-end open source platform for machine learning. In affected versions the implementation of `tf.raw_ops.SparseReshape` can be made to trigger an integral division by 0 exception. The [implementation](https://github.com/tensorflow/tensorflow/blob/8d72537c6abf5a44103b57b9c2e22c14f5f49698/tensorflow/core/kernels/reshape_util.cc#L176-L181) calls the reshaping functor whenever there is at least an index in the input but does not check that shape of the input or the target shape have both a non-zero number of elements. The [reshape functor](https://github.com/tensorflow/tensorflow/blob/8d72537c6abf5a44103b57b9c2e22c14f5f49698/tensorflow/core/kernels/reshape_util.cc#L40-L78) blindly divides by the dimensions of the target shape. Hence, if this is not checked, code will result in a division by 0. We have patched the issue in GitHub commit 4923de56ec94fff7770df259ab7f2288a74feb41. The fix will be included in TensorFlow 2.6.0. We will also cherrypick this commit on TensorFlow 2.5.1 as this is the other affected version.

MediumCVSS 5.5 · v3.1—No exploit Fix available
Published
Aug 12, 2021
Updated
Jun 17, 2026
EPSS
0.1% · 4th percentile

Report tools

JSON

Action score

22

Monitor

Low priority for now.

CVSS
22 / 40 · 5.5 / 10
CISA KEV
0 / 30 · Not listed
EPSS
0 / 30 · 0.1%

CNA vs NVD score

NVD
5.5
CNA · GitHub_M
5.5
agree

The score given by the assigning authority versus NVD’s independent score. A gap means the severity is contested.

Get told when this record changes

  • Not in KEV: no record of exploitation in the wild
  • No public exploit code on record
  • A fix has been released

If any of these changes, we'll tell you in the daily email digest.

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When you'll hear from us

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  • when exploit code appears or is weaponized
  • when the record is updated (including a fixed version)
  • when EPSS rises 20 points in a week

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Noroxi analysis

What does it mean in your environment?

The assessment above is generated automatically from the record's data; it doesn't know your environment. Our team verifies on your systems whether this vulnerability is actually exploitable and which mitigation is enough.

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Affected systems

Is your version affected?

Pick the product and type the version you run. It's compared with this record's version ranges in your browser; the version isn't sent anywhere.

VendorProduct
googletensorflow

Affected versions

NVD version ranges (for catalog products). Add the product to your stack with a version and matching uses these.

  • google tensorflow2.3.0 and later · before 2.3.4
  • google tensorflow2.4.0 and later · before 2.4.3
  • google tensorflow2.5.0
  • google tensorflow2.6.0

Versions reported by the vendor

Affected version ranges reported by the assigning authority (GitHub_M). Independent of NVD's CPE analysis and usually ahead of it.

  • tensorflow tensorflow

    • < 2.5.1affected

Package-level exposure

OSV and GitHub Advisory data: ecosystem, package and range. SBOM matching uses this table.

EcosystemPackageAffected rangeFix
openSUSE:Leap 15.3bazel-skylib1.0.3before 1.0.3-bp153.2.11.0.3-bp153.2.1
openSUSE:Leap 15.3bazel3.7before 3.7.2-bp153.4.13.7.2-bp153.4.1
openSUSE:Leap 15.3tensorflow2before 2.6.0-bp153.2.3.12.6.0-bp153.2.3.1
openSUSE:Leap 15.3tensorflow2_2_6_0-gnu-hpcbefore 2.6.0-bp153.2.3.12.6.0-bp153.2.3.1
openSUSE:Leap 15.3tensorflow2_2_6_0-gnu-openmpi2-hpcbefore 2.6.0-bp153.2.3.12.6.0-bp153.2.3.1
openSUSE:Leap 15.3tensorflow2-litebefore 2.6.0-bp153.2.3.12.6.0-bp153.2.3.1
PyPItensorflowfrom 2.3.0 · before 2.3.42.3.4
PyPItensorflowfrom 2.4.0 · before 2.4.32.4.3
PyPItensorflowfrom 2.5.0 · before 2.5.12.5.1
PyPItensorflowbefore 2.3.42.3.4
PyPItensorflow-cpufrom 2.3.0 · before 2.3.42.3.4
PyPItensorflow-cpufrom 2.4.0 · before 2.4.32.4.3
PyPItensorflow-cpufrom 2.5.0 · before 2.5.12.5.1
PyPItensorflow-cpubefore 2.3.42.3.4
PyPItensorflow-gpufrom 2.3.0 · before 2.3.42.3.4
PyPItensorflow-gpufrom 2.4.0 · before 2.4.32.4.3
PyPItensorflow-gpufrom 2.5.0 · before 2.5.12.5.1
PyPItensorflow-gpubefore 2.3.42.3.4
SUSE:Package Hub 15 SP3bazel-skylib1.0.3before 1.0.3-bp153.2.11.0.3-bp153.2.1
SUSE:Package Hub 15 SP3bazel3.7before 3.7.2-bp153.4.13.7.2-bp153.4.1
SUSE:Package Hub 15 SP3tensorflow2before 2.6.0-bp153.2.3.12.6.0-bp153.2.3.1
SUSE:Package Hub 15 SP3tensorflow2_2_6_0-gnu-hpcbefore 2.6.0-bp153.2.3.12.6.0-bp153.2.3.1
SUSE:Package Hub 15 SP3tensorflow2_2_6_0-gnu-openmpi2-hpcbefore 2.6.0-bp153.2.3.12.6.0-bp153.2.3.1
SUSE:Package Hub 15 SP3tensorflow2-litebefore 2.6.0-bp153.2.3.12.6.0-bp153.2.3.1

Same product

google: all records

Other highest-scoring records for the same primary product.

  • CVE-2023-25668TensorFlow vulnerable to heap out-of-buffer read in the QuantizeAndDequantize operation
    39Monitor
  • CVE-2023-25664TensorFlow vulnerable to Heap Buffer Overflow in AvgPoolGrad
    39Monitor
  • CVE-2022-41900FractionalMaxPool and FractionalAVGPool heap out-of-bounds acess in Tensorflow
    39Monitor

Published before and after this one in the same product

  • ← EarlierCVE-2021-35958Jun 29, 2021 · TensorFlow through 2.5.0 allows attackers to overwrite arbitrary files via a crafted archive when tf.keras.utils.get_file is used with extra
    37Monitor
  • ← EarlierCVE-2021-37636Aug 12, 2021 · Floating point exception in `SparseDenseCwiseDiv` in TensorFlow
    22Monitor
  • Later →CVE-2021-37642Aug 12, 2021 · Division by 0 in `ResourceScatterDiv` in TensorFlow
    22Monitor

Remediation

Which version to upgrade to

Fix versions compiled from the vendor, package registries and Microsoft. Verify the vendor's note before upgrading.

Product / packageFixed versionSource
opensuse:bazel-skylib1.0.31.0.3-bp153.2.1 · openSUSE:Leap 15.3Package registry (OSV)
opensuse:bazel3.73.7.2-bp153.4.1 · openSUSE:Leap 15.3Package registry (OSV)
opensuse:tensorflow22.6.0-bp153.2.3.1 · openSUSE:Leap 15.3Package registry (OSV)
opensuse:tensorflow2_2_6_0-gnu-hpc2.6.0-bp153.2.3.1 · openSUSE:Leap 15.3Package registry (OSV)
opensuse:tensorflow2_2_6_0-gnu-openmpi2-hpc2.6.0-bp153.2.3.1 · openSUSE:Leap 15.3Package registry (OSV)
opensuse:tensorflow2-lite2.6.0-bp153.2.3.1 · openSUSE:Leap 15.3Package registry (OSV)
PyPI:tensorflow2.3.4Package registry (OSV)
PyPI:tensorflow2.4.3Package registry (OSV)
PyPI:tensorflow2.5.1Package registry (OSV)
PyPI:tensorflow-cpu2.3.4Package registry (OSV)
PyPI:tensorflow-cpu2.4.3Package registry (OSV)
PyPI:tensorflow-cpu2.5.1Package registry (OSV)
PyPI:tensorflow-gpu2.3.4Package registry (OSV)
PyPI:tensorflow-gpu2.4.3Package registry (OSV)
PyPI:tensorflow-gpu2.5.1Package registry (OSV)
suse:bazel-skylib1.0.31.0.3-bp153.2.1 · SUSE:Package Hub 15 SP3Package registry (OSV)
suse:bazel3.73.7.2-bp153.4.1 · SUSE:Package Hub 15 SP3Package registry (OSV)
suse:tensorflow22.6.0-bp153.2.3.1 · SUSE:Package Hub 15 SP3Package registry (OSV)
suse:tensorflow2_2_6_0-gnu-hpc2.6.0-bp153.2.3.1 · SUSE:Package Hub 15 SP3Package registry (OSV)
suse:tensorflow2_2_6_0-gnu-openmpi2-hpc2.6.0-bp153.2.3.1 · SUSE:Package Hub 15 SP3Package registry (OSV)
suse:tensorflow2-lite2.6.0-bp153.2.3.1 · SUSE:Package Hub 15 SP3Package registry (OSV)

Exploit status

No known public exploit

No public exploit has been observed yet. That doesn't mean you're safe, only that the bar is a little higher.

Research context

For pentesters and researchers: attack profile, score disagreement, timeline, patch commits, credits, variant and chain candidates, bug bounty scope. All derived from existing data; no exploit code.

Timeline

From publication to today: proof of concept, Metasploit module, CISA KEV and fix record. Dates are as reported by the sources.

No dated events beyond publication.

No history yet (it accumulates with the daily EPSS job).

Patch and commit links

Commit, PR and diff links among the references. A starting point for patch-diffing and variant hunting; fixes, not exploits.

Credits

All researchers

Finders, reporters and analysts named in the CNA record. Click a name for that researcher’s other records.

No credits in the CNA record.

Variant candidates

Same product, same weakness class, within 18 months. If the patch missed the root cause, the sibling bug is here.

No nightly-computed relations.

Chain candidates

An authentication bypass and a privilege-requiring bug in the same product, published close together: combined they may become an unauthenticated path.

—

Bug bounty scope

No known public program.

Source: bounty-targets-data (public HackerOne, Bugcrowd, Intigriti, YesWeHack listings).

Technical details

Attack conditions

  • Someone with local access to the system can trigger it.
  • A low-privileged account is enough.
  • No user action is required.
  • No special conditions are required; it is repeatable.

If successful

Confidentiality
none
Integrity
none
Availability
high · the service can be disrupted
Attack vector
Local
Attack complexity
Low
Privileges required
Low
User interaction
None
Scope
Unchanged
Confidentiality impact
None
Integrity impact
None
Availability impact
High

Weakness class (CWE)

CWE-369 · Divide By Zero

CVSS vector

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

nvd-primary

Attack context

MITRE CAPEC attack patterns and ATT&CK techniques for this weakness class (CWE). A starting point for detection rules and threat hunting.

MITRE has no CAPEC/ATT&CK mapping for this CWE.

Change log

  1. Fix✗ → ✓

For records you follow, these changes also arrive as notifications. →

References

Show all references (1 more)

Vendor advisories and official records. Exploit/PoC links are deliberately left out.

All records