Stack overflow due to looping TFLite subgraph
High7.3CVE-2021-29591 · 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 TFlite graphs must not have loops between nodes. However, this condition was not checked and an attacker could craft models that would result in infinite loop during evaluation. In certain cases, the infinite loop would be replaced by stack overflow due to too many recursive calls. For example, the [`While` implementation](https://github.com/tensorflow/tensorflow/blob/106d8f4fb89335a2c52d7c895b7a7485465ca8d9/tensorflow/lite/kernels/while.cc) could be tricked into a scneario where both the body and the loop subgraphs are the same. Evaluating one of the subgraphs means calling the `Eval` function for the other and this quickly exhaust all stack space. ### Patches We have patched the issue in GitHub commit [9c1dc920d8ffb4893d6c9d27d1f039607b326743](https://github.com/tensorflow/tensorflow/commit/9c1dc920d8ffb4893d6c9d27d1f039607b326743) (for the `While` operator) and in GitHub commit [c6173f5fe66cdbab74f4f869311fe6aae2ba35f4](https://github.com/tensorflow/tensorflow/commit/c6173f5fe66cdbab74f4f869311fe6aae2ba35f4) (in general). 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:L/PR:L/UI:N/S:U/C:H/I:L/A:H
- Severity from
- GitHub (reviewed advisory)
- Weakness
- CWE-674, CWE-835
- Also known as
- BIT-tensorflow-2021-29591, CVE-2021-29591, PYSEC-2021-228, PYSEC-2021-519, PYSEC-2021-717
- github.com/tensorflow/tensorflow/security/advisories/GHSA-cwv3-863g-39vx
- nvd.nist.gov/vuln/detail/CVE-2021-29591
- github.com/tensorflow/tensorflow/commit/9c1dc920d8ffb4893d6c9d27d1f039607b326743
- github.com/tensorflow/tensorflow/commit/c6173f5fe66cdbab74f4f869311fe6aae2ba35f4
- github.com/pypa/advisory-database/tree/main/vulns/tensorflow-cpu/PYSEC-2021-519.yaml
- github.com/pypa/advisory-database/tree/main/vulns/tensorflow-gpu/PYSEC-2021-717.yaml
- github.com/pypa/advisory-database/tree/main/vulns/tensorflow/PYSEC-2021-228.yaml
- github.com/tensorflow/tensorflow
- github.com/tensorflow/tensorflow/blob/106d8f4fb89335a2c52d7c895b7a7485465ca8d9/tensorflow/lite/kernels/while.cc
More TensorFlow advisories
All TensorFlow| Date | Advisory | Severity | Fixed in |
|---|---|---|---|
| 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 |