Low

OOB read in `MatrixTriangularSolve`

  • Disclosed: 14.05.2021
  • Updated: 11.10.2026 13:19

Impact

The implementation of MatrixTriangularSolve fails to terminate kernel execution if one validation condition fails:

cc
void ValidateInputTensors(OpKernelContext* ctx, const Tensor& in0,
                            const Tensor& in1) override {
  OP_REQUIRES(
      ctx, in0.dims() >= 2,
      errors::InvalidArgument("In[0] ndims must be >= 2: ", in0.dims()));

  OP_REQUIRES(
      ctx, in1.dims() >= 2,
      errors::InvalidArgument("In[0] ndims must be >= 2: ", in1.dims()));
}
  
void Compute(OpKernelContext* ctx) override {
  const Tensor& in0 = ctx->input(0);
  const Tensor& in1 = ctx->input(1);

  ValidateInputTensors(ctx, in0, in1);

  MatMulBCast bcast(in0.shape().dim_sizes(), in1.shape().dim_sizes());
  ...
}

Since OP_REQUIRES only sets ctx->status() to a non-OK value and calls return, this allows malicious attackers to trigger an out of bounds read:

python
import tensorflow as tf
import numpy as np

matrix_array = np.array([])
matrix_tensor = tf.convert_to_tensor(np.reshape(matrix_array,(1,0)),dtype=tf.float32)
rhs_array = np.array([])
rhs_tensor = tf.convert_to_tensor(np.reshape(rhs_array,(0,1)),dtype=tf.float32)

tf.raw_ops.MatrixTriangularSolve(matrix=matrix_tensor,rhs=rhs_tensor,lower=False,adjoint=False)

As the two input tensors are empty, the OP_REQUIRES in ValidateInputTensors should fire and interrupt execution. However, given the implementation of OP_REQUIRES, after the in0.dims() >= 2 fails, execution moves to the initialization of the bcast object. This initialization is done with invalid data and results in heap OOB read.

Patches

We have patched the issue in GitHub commit 480641e3599775a8895254ffbc0fc45621334f68.

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.

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 Ye Zhang and Yakun Zhang of Baidu X-Team.

Affected software

Click a technology to see all vulnerabilities affecting it.

PlatformPackageVulnerable versionsFixed in
Python (PyPI) tensorflow < 2.1.4, >= 2.2.0, < 2.2.3, >= 2.3.0, < 2.3.3, >= 2.4.0, < 2.4.2 2.1.4, 2.2.3, 2.3.3, 2.4.2
Python (PyPI) tensorflow-cpu < 2.1.4, >= 2.2.0, < 2.2.3, >= 2.3.0, < 2.3.3, >= 2.4.0, < 2.4.2 2.1.4, 2.2.3, 2.3.3, 2.4.2
Python (PyPI) tensorflow-gpu < 2.1.4, >= 2.2.0, < 2.2.3, >= 2.3.0, < 2.3.3, >= 2.4.0, < 2.4.2 2.1.4, 2.2.3, 2.3.3, 2.4.2

References

CVSS score 2.5/10
CVSS vector
CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:N/I:N/A:L
Weakness (CWE)
CWE-125
Platform
Python (PyPI)
Package
tensorflow, tensorflow-cpu, tensorflow-gpu
Disclosed
14.05.2021
Updated
11.10.2026 13:19

Sources and licenses

OSV / GitHub Advisory Database - PYSEC-2021-188 - PyPA Advisory Database; CC BY 4.0

OSV / GitHub Advisory Database - PYSEC-2021-479 - PyPA Advisory Database; CC BY 4.0

OSV / GitHub Advisory Database - PYSEC-2021-677 - PyPA Advisory Database; CC BY 4.0

OSV / GitHub Advisory Database - GHSA-vqw6-72r7-fgw7 - 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. OOB read in `MatrixTriangularSolve` this entry
    Low · 2.5 CVE-2021-29551 < 2.1.4, >= 2.2.0, < 2.2.3, >= 2.3.0, < 2.3.3, >= 2.4.0, < 2.4.2 2.1.4, 2.2.3, 2.3.3, 2.4.2
  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
Show more (20) Showing 21 of 119

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