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Fencer Vulns
high 8.4

CVE-2021-37639 json

Null pointer dereference and heap OOB read in TensorFlow

published 2021-08-12 5 y ago modified 2026-09-08 2 mo ago also BIT-tensorflow-2021-37639 , EUVD-2021-0365 , GHSA-gh6x-4whr-2qv4 , PYSEC-2021-261 , PYSEC-2021-552 , PYSEC-2021-750

cvss
8.4
version 3.1, CNA
cisa kev
Not listed
not in CISA's catalog
epss
0.2%
EPSS 0.2% chance of exploitation in 30 days, percentile 6%
public exploits
0
none known

Summary

TensorFlow is an end-to-end open source platform for machine learning. When restoring tensors via raw APIs, if the tensor name is not provided, TensorFlow can be tricked into dereferencing a null pointer. Alternatively, attackers can read memory outside the bounds of heap allocated data by providing some tensor names but not enough for a successful restoration. The [implementation](https://github.com/tensorflow/tensorflow/blob/47a06f40411a69c99f381495f490536972152ac0/tensorflow/core/kernels/save_restore_tensor.cc#L158-L159) retrieves the tensor list corresponding to the `tensor_name` user controlled input and immediately retrieves the tensor at the restoration index (controlled via `preferred_shard` argument). This occurs without validating that the provided list has enough values. If the list is empty this results in dereferencing a null pointer (undefined behavior). If, however, the list has some elements, if the restoration index is outside the bounds this results in heap OOB read. We have patched the issue in GitHub commit 9e82dce6e6bd1f36a57e08fa85af213e2b2f2622. The fix will be included in TensorFlow 2.6.0. We will also cherrypick this commit on TensorFlow 2.5.1, TensorFlow 2.4.3, and TensorFlow 2.3.4, as these are also affected and still in supported range.

Patch / fix

  • pypi tensorflow 2.3.4, 2.4.3, 2.5.1
  • pypi tensorflow-cpu 2.3.4, 2.4.3, 2.5.1
  • pypi tensorflow-gpu 2.3.4, 2.4.3, 2.5.1
  • bitnami tensorflow 2.3.4, 2.4.3, 2.5.1
  • google tensorflow 2.3.4, 2.4.3
  • tensorflow2 Package Hub 15 SP3, openSUSE Leap 15.3 2.6.0-bp153.2.3.1
  • bazel3.7 Package Hub 15 SP3, openSUSE Leap 15.3 3.7.2-bp153.4.1
  • tensorflow2-lite Package Hub 15 SP3, openSUSE Leap 15.3 2.6.0-bp153.2.3.1
  • bazel-skylib1.0.3 Package Hub 15 SP3, openSUSE Leap 15.3 1.0.3-bp153.2.1
  • tensorflow2_2_6_0-gnu-hpc Package Hub 15 SP3, openSUSE Leap 15.3 2.6.0-bp153.2.3.1
  • tensorflow2_2_6_0-gnu-openmpi2-hpc Package Hub 15 SP3, openSUSE Leap 15.3 2.6.0-bp153.2.3.1

opensuse advisories openSUSE-SU-2022:10014-1

  • tensorflow Arch Linux 2.5.1-1

arch linux advisories AVG-2292

Exploit prediction

0.17% chance of exploitation in the next 30 days, higher than 6% of all scored CVEs (FIRST EPSS, 2026-11-08).

CVSS scores

assigned by version score vector
CNA 3.1 8.4 CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
GitHub 3.1 8.4 CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
NVD 3.1 7.8 CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
NVD 2.0 4.6 AV:L/AC:L/Au:N/C:P/I:P/A:P
OSV 3.1 7.8 CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

Affected packages

ecosystem package affected fixed in
pypi tensorflow
<2.3.4
>=2.4.0, <2.4.3
>=2.5.0, <2.5.1
>=2.3.0, <2.3.4
2.3.4
2.4.3
2.5.1
pypi tensorflow-cpu
<2.3.4
>=2.4.0, <2.4.3
>=2.5.0, <2.5.1
>=2.3.0, <2.3.4
2.3.4
2.4.3
2.5.1
pypi tensorflow-gpu
<2.3.4
>=2.4.0, <2.4.3
>=2.5.0, <2.5.1
>=2.3.0, <2.3.4
2.3.4
2.4.3
2.5.1
bitnami tensorflow
>=2.3.0, <2.3.4
>=2.4.0, <2.4.3
>=2.5.0, <2.5.1
2.3.4
2.4.3
2.5.1

Affected products

  • tensorflow tensorflow

Classification

Weakness

References

Sources

Fencer Vulns keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.