High

Heap OOB in nested `tf.map_fn` with `RaggedTensor`s

  • Disclosed: 12.08.2021
  • Updated: 11.10.2026 13:19

Impact

It is possible to nest a tf.map_fn within another tf.map_fn call. However, if the input tensor is a RaggedTensor and there is no function signature provided, code assumes the output is a fully specified tensor and fills output buffer with uninitialized contents from the heap:

python
import tensorflow as tf
x = tf.ragged.constant([[1,2,3], [4,5], [6]])
t = tf.map_fn(lambda r: tf.map_fn(lambda y: r, r), x)
z = tf.ragged.constant([[[1,2,3],[1,2,3],[1,2,3]],[[4,5],[4,5]],[[6]]])

The t and z outputs should be identical, however this is not the case. The last row of t contains data from the heap which can be used to leak other memory information.

The bug lies in the conversion from a Variant tensor to a RaggedTensor. The implementation does not check that all inner shapes match and this results in the additional dimensions in the above example.

The same implementation can result in data loss, if input tensor is tweaked:

python
import tensorflow as tf
x = tf.ragged.constant([[1,2], [3,4,5], [6]])
t = tf.map_fn(lambda r: tf.map_fn(lambda y: r, r), x)

Here, the output tensor will only have 2 elements for each inner dimension.

Patches

We have patched the issue in GitHub commit 4e2565483d0ffcadc719bd44893fb7f609bb5f12.

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.

For more information

Please consult our security guide for more information regarding the security model and how to contact us with issues and questions.

Attribution

This vulnerability has been reported by Haris Sahovic.

Affected software

Click a technology to see all vulnerabilities affecting it.

PlatformPackageVulnerable versionsFixed in
Python (PyPI) tensorflow < 2.3.4, >= 2.4.0, < 2.4.3, >= 2.5.0, < 2.5.1 2.3.4, 2.4.3, 2.5.1
Python (PyPI) tensorflow-cpu < 2.3.4, >= 2.4.0, < 2.4.3, >= 2.5.0, < 2.5.1 2.3.4, 2.4.3, 2.5.1
Python (PyPI) tensorflow-gpu < 2.3.4, >= 2.4.0, < 2.4.3, >= 2.5.0, < 2.5.1 2.3.4, 2.4.3, 2.5.1

References

CVSS score 7.1/10
CVSS vector
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:N
Weakness (CWE)
CWE-125, CWE-681
Platform
Python (PyPI)
Package
tensorflow, tensorflow-cpu, tensorflow-gpu
Disclosed
12.08.2021
Updated
11.10.2026 13:19

Sources and licenses

OSV / GitHub Advisory Database - PYSEC-2021-301 - PyPA Advisory Database; CC BY 4.0

OSV / GitHub Advisory Database - PYSEC-2021-592 - PyPA Advisory Database; CC BY 4.0

OSV / GitHub Advisory Database - PYSEC-2021-790 - PyPA Advisory Database; CC BY 4.0

OSV / GitHub Advisory Database - GHSA-g8wg-cjwc-xhhp - CC BY 4.0

Vulnerability history: tensorflow

All published vulnerabilities of this package (Python (PyPI)), newest first. Shows whether this is a one-off slip or a package that needs watching.

All (433) in the archive
Total entries
433
First → latest
04.2019 07.2024
Without a fix
0
Exploited in attacks
0

Severity breakdown

  • Critical 6
  • High 112
  • Medium 210
  • Low 105

Disclosures per year

  1. 2019: 7
  2. 2020: 35
  3. 2021: 200
  4. 2022: 169
  5. 2023: 21
  6. 2024: 1
  7. 2025: 0
  8. 2026: 0
Severity:
  1. Heap OOB in nested `tf.map_fn` with `RaggedTensor`s this entry
    High · 7.1 CVE-2021-37679 < 2.3.4, >= 2.4.0, < 2.4.3, >= 2.5.0, < 2.5.1 2.3.4, 2.4.3, 2.5.1
  2. High · 7.5 CVE-2023-33976 < 2.12.1 2.12.1
  3. High · 7.5 CVE-2023-25659 < 2.11.1 2.11.1
  4. High · 7.5 CVE-2023-25660 < 2.11.1 2.11.1
  5. High · 7.5 CVE-2023-25662 < 2.11.1 2.11.1
  6. High · 7.5 CVE-2023-25663 < 2.11.1 2.11.1
  7. High · 7.5 CVE-2023-25664 < 2.11.1 2.11.1
  8. High · 7.5 CVE-2023-25665 < 2.11.1 2.11.1
  9. High · 7.5 CVE-2023-25666 < 2.11.1 2.11.1
  10. High · 7.5 CVE-2023-25669 < 2.11.1 2.11.1
  11. High · 7.5 CVE-2023-25671 < 2.11.1 2.11.1
  12. High · 7.5 CVE-2023-25672 < 2.11.1 2.11.1
  13. High · 7.5 CVE-2023-25673 < 2.11.1 2.11.1
  14. High · 7.5 CVE-2023-25674 < 2.11.1 2.11.1
  15. High · 7.5 CVE-2023-25675 < 2.11.1 2.11.1
  16. High · 7.5 CVE-2023-25676 < 2.11.1 2.11.1
  17. High · 8.0 CVE-2023-25801 < 2.11.1 2.11.1
  18. High · 7.5 CVE-2023-27579 < 2.11.1 2.11.1
  19. High · 7.5 CVE-2023-25658 < 2.11.1 2.11.1
  20. High · 7.1 CVE-2022-41902 < 2.8.4, >= 2.9.0, < 2.9.3, >= 2.10.0, < 2.10.1 2.8.4, 2.9.3, 2.10.1
  21. High · 7.1 CVE-2022-41900 < 2.8.4, >= 2.9.0, < 2.9.3, >= 2.10.0, < 2.10.1 2.8.4, 2.9.3, 2.10.1
  22. High · 7.1 CVE-2022-41894 < 2.8.4, >= 2.9.0, < 2.9.3, >= 2.10.0, < 2.10.1 2.8.4, 2.9.3, 2.10.1
  23. High · 7.0 CVE-2022-35939 < 2.7.2, >= 2.8.0, < 2.8.1, >= 2.9.0, < 2.9.1 2.7.2, 2.8.1, 2.9.1
  24. High · 7.0 CVE-2022-35937 < 2.7.2, >= 2.8.0, < 2.8.1, >= 2.9.0, < 2.9.1 2.7.2, 2.8.1, 2.9.1
  25. High · 7.8 CVE-2022-29216 < 2.6.4, >= 2.7.0, < 2.7.2, >= 2.8.0, < 2.8.1 2.6.4, 2.7.2, 2.8.1
  26. High · 7.1 CVE-2022-29208 < 2.6.4, >= 2.7.0, < 2.7.2, >= 2.8.0, < 2.8.1 2.6.4, 2.7.2, 2.8.1
  27. Critical · 9.3 ghsa-h6gw-r52c-724r < 2.5.3, >= 2.6.0, < 2.6.3, >= 2.7.0, < 2.7.1 2.5.3, 2.6.3, 2.7.1
  28. High · 7.0 ghsa-43q8-3fv7-pr5x < 2.5.3, >= 2.6.0, < 2.6.3, >= 2.7.0, < 2.7.1 2.5.3, 2.6.3, 2.7.1
  29. High · 8.8 CVE-2022-23594 >= 2.7.0, < 2.7.1 2.7.1
  30. High · 8.8 CVE-2022-23560 < 2.5.3, >= 2.6.0, < 2.6.3, >= 2.7.0, < 2.7.1 2.5.3, 2.6.3, 2.7.1
  31. High · 7.1 CVE-2022-23563 < 2.5.3, >= 2.6.0, < 2.6.3, >= 2.7.0, < 2.7.1 2.5.3, 2.6.3, 2.7.1
  32. High · 8.1 CVE-2022-23592 >= 2.8.0-rc0, < 2.8.0 2.8.0
  33. High · 7.5 CVE-2022-23591 < 2.5.3, >= 2.6.0, < 2.6.3, >= 2.7.0, < 2.7.1 2.5.3, 2.6.3, 2.7.1
  34. High · 8.8 CVE-2022-23574 < 2.5.3, >= 2.6.0, < 2.6.3, >= 2.7.0, < 2.7.1 2.5.3, 2.6.3, 2.7.1
  35. High · 7.6 CVE-2022-23573 < 2.5.3, >= 2.6.0, < 2.6.3, >= 2.7.0, < 2.7.1 2.5.3, 2.6.3, 2.7.1
  36. High · 7.6 CVE-2022-23562 < 2.5.3, >= 2.6.0, < 2.6.3, >= 2.7.0, < 2.7.1 2.5.3, 2.6.3, 2.7.1
  37. High · 8.8 CVE-2022-23561 < 2.5.3, >= 2.6.0, < 2.6.3, >= 2.7.0, < 2.7.1 2.5.3, 2.6.3, 2.7.1
  38. High · 8.8 CVE-2022-23559 < 2.5.3, >= 2.6.0, < 2.6.3, >= 2.7.0, < 2.7.1 2.5.3, 2.6.3, 2.7.1
  39. High · 8.8 CVE-2022-23566 < 2.5.3, >= 2.6.0, < 2.6.3, >= 2.7.0, < 2.7.1 2.5.3, 2.6.3, 2.7.1
  40. High · 7.6 CVE-2022-23584 < 2.5.3, >= 2.6.0, < 2.6.3, >= 2.7.0, < 2.7.1 2.5.3, 2.6.3, 2.7.1
  41. High · 7.6 CVE-2022-23558 < 2.5.3, >= 2.6.0, < 2.6.3, >= 2.7.0, < 2.7.1 2.5.3, 2.6.3, 2.7.1
  42. High · 8.8 CVE-2022-23587 < 2.5.3, >= 2.6.0, < 2.6.3, >= 2.7.0, < 2.7.1 2.5.3, 2.6.3, 2.7.1
  43. High · 7.6 CVE-2022-21740 < 2.5.3, >= 2.6.0, < 2.6.3, >= 2.7.0, < 2.7.1 2.5.3, 2.6.3, 2.7.1
  44. High · 6.5 CVE-2022-21741 < 2.5.3, >= 2.6.0, < 2.6.3, >= 2.7.0, < 2.7.1 2.5.3, 2.6.3, 2.7.1
  45. High · 6.5 CVE-2022-21739 < 2.5.3, >= 2.6.0, < 2.6.3, >= 2.7.0, < 2.7.1 2.5.3, 2.6.3, 2.7.1
  46. High · 6.5 CVE-2022-21737 < 2.5.3, >= 2.6.0, < 2.6.3, >= 2.7.0, < 2.7.1 2.5.3, 2.6.3, 2.7.1
  47. High · 6.5 CVE-2022-21738 < 2.5.3, >= 2.6.0, < 2.6.3, >= 2.7.0, < 2.7.1 2.5.3, 2.6.3, 2.7.1
  48. High · 6.5 CVE-2022-23569 < 2.5.3, >= 2.6.0, < 2.6.3, >= 2.7.0, < 2.7.1 2.5.3, 2.6.3, 2.7.1
  49. High · 6.5 CVE-2022-21729 < 2.5.3, >= 2.6.0, < 2.6.3, >= 2.7.0, < 2.7.1 2.5.3, 2.6.3, 2.7.1
  50. High · 6.5 CVE-2022-21734 < 2.5.3, >= 2.6.0, < 2.6.3, >= 2.7.0, < 2.7.1 2.5.3, 2.6.3, 2.7.1
  51. High · 6.5 CVE-2022-21735 < 2.5.3, >= 2.6.0, < 2.6.3, >= 2.7.0, < 2.7.1 2.5.3, 2.6.3, 2.7.1
  52. High · 7.6 CVE-2022-21736 < 2.5.3, >= 2.6.0, < 2.6.3, >= 2.7.0, < 2.7.1 2.5.3, 2.6.3, 2.7.1
  53. High · 6.5 CVE-2022-21731 < 2.5.3, >= 2.6.0, < 2.6.3, >= 2.7.0, < 2.7.1 2.5.3, 2.6.3, 2.7.1
  54. High · 6.5 CVE-2022-23567 < 2.5.3, >= 2.6.0, < 2.6.3, >= 2.7.0, < 2.7.1 2.5.3, 2.6.3, 2.7.1
  55. High · 6.5 CVE-2022-23568 < 2.5.3, >= 2.6.0, < 2.6.3, >= 2.7.0, < 2.7.1 2.5.3, 2.6.3, 2.7.1
  56. High · 8.1 CVE-2022-21726 < 2.5.3, >= 2.6.0, < 2.6.3, >= 2.7.0, < 2.7.1 2.5.3, 2.6.3, 2.7.1
  57. High · 8.1 CVE-2022-21728 < 2.5.3, >= 2.6.0, < 2.6.3, >= 2.7.0, < 2.7.1 2.5.3, 2.6.3, 2.7.1
  58. High · 7.6 CVE-2022-21727 < 2.5.3, >= 2.6.0, < 2.6.3, >= 2.7.0, < 2.7.1 2.5.3, 2.6.3, 2.7.1
  59. High · 8.1 CVE-2022-21730 < 2.5.3, >= 2.6.0, < 2.6.3, >= 2.7.0, < 2.7.1 2.5.3, 2.6.3, 2.7.1
Show more (20) Showing 61 of 118

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