Division by zero in TFLite's implementation of `DepthToSpace`
Low2.5CVE-2021-29595 · Published May 21, 2021 · updated Jul 8, 2026
Affected versions
| Package | Affected | Fixed in |
|---|---|---|
| tensorflow PyPI | < 2.1.4 | 2.1.4 |
| >= 2.2.0, < 2.2.3 | 2.2.3 | |
| >= 2.3.0, < 2.3.3 | 2.3.3 | |
| >= 2.4.0, < 2.4.2 | 2.4.2 |
Details and references
### Impact The implementation of the `DepthToSpace` TFLite operator is [vulnerable to a division by zero error](https://github.com/tensorflow/tensorflow/blob/0d45ea1ca641b21b73bcf9c00e0179cda284e7e7/tensorflow/lite/kernels/depth_to_space.cc#L63-L69): ```cc const int block_size = params->block_size; ... const int input_channels = input->dims->data[3]; ... int output_channels = input_channels / block_size / block_size; ``` An attacker can craft a model such that `params->block_size` is 0. ### Patches We have patched the issue in GitHub commit [106d8f4fb89335a2c52d7c895b7a7485465ca8d9](https://github.com/tensorflow/tensorflow/commit/106d8f4fb89335a2c52d7c895b7a7485465ca8d9). 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](https://github.com/tensorflow/tensorflow/blob/master/SECURITY.md) for more information regarding the security model and how to contact us with issues and questions. ### Attribution This vulnerability has been reported by members of the Aivul Team from Qihoo 360.
- CVSS 3.1
- CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:N/I:N/A:L
- Severity from
- GitHub (reviewed advisory)
- Weakness
- CWE-369
- Also known as
- BIT-tensorflow-2021-29595, CVE-2021-29595, PYSEC-2021-232, PYSEC-2021-523, PYSEC-2021-721
- github.com/tensorflow/tensorflow/security/advisories/GHSA-vf94-36g5-69v8
- nvd.nist.gov/vuln/detail/CVE-2021-29595
- github.com/tensorflow/tensorflow/commit/106d8f4fb89335a2c52d7c895b7a7485465ca8d9
- github.com/pypa/advisory-database/tree/main/vulns/tensorflow-cpu/PYSEC-2021-523.yaml
- github.com/pypa/advisory-database/tree/main/vulns/tensorflow-gpu/PYSEC-2021-721.yaml
- github.com/pypa/advisory-database/tree/main/vulns/tensorflow/PYSEC-2021-232.yaml
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|---|---|---|---|
| May 212021 | Heap buffer overflow in `RaggedBinCount` CVE-2021-29512Low2.5fixed in 2.3.3, 2.4.2 | Low2.5 | 2.3.3, 2.4.2 |
| May 212021 | Type confusion during tensor casts lead to dereferencing null pointers CVE-2021-29513Low2.5fixed in 2.1.4, 2.2.3, 2.3.3, 2.4.2 | Low2.5 | 2.1.4, 2.2.3, 2.3.3, 2.4.2 |
| May 212021 | Heap out of bounds write in `RaggedBinCount` CVE-2021-29514Low2.5fixed in 2.3.3, 2.4.2 | Low2.5 | 2.3.3, 2.4.2 |
| May 212021 | Reference binding to null pointer in `MatrixDiag*` ops CVE-2021-29515Low2.5fixed in 2.1.4, 2.2.3, 2.3.3, 2.4.2 | Low2.5 | 2.1.4, 2.2.3, 2.3.3, 2.4.2 |
| May 212021 | Null pointer dereference via invalid Ragged Tensors CVE-2021-29516Low2.5fixed in 2.1.4, 2.2.3, 2.3.3, 2.4.2 | Low2.5 | 2.1.4, 2.2.3, 2.3.3, 2.4.2 |
| May 212021 | Division by zero in `Conv3D` CVE-2021-29517Low2.5fixed in 2.1.4, 2.2.3, 2.3.3, 2.4.2 | Low2.5 | 2.1.4, 2.2.3, 2.3.3, 2.4.2 |