Heap OOB in shape inference for `QuantizeV2`
High7.1CVE-2021-41211 · Published Nov 10, 2021 · updated Jul 8, 2026
### Impact The [shape inference code for `QuantizeV2`](https://github.com/tensorflow/tensorflow/blob/8d72537c6abf5a44103b57b9c2e22c14f5f49698/tensorflow/core/framework/common_shape_fns.cc#L2509-L2530) can trigger a read outside of bounds of heap allocated array: ```python import tensorflow as tf @tf.function def test(): data=tf.raw_ops.QuantizeV2( input=[1.0,1.0], min_range=[1.0,10.0], max_range=[1.0,10.0], T=tf.qint32, mode='MIN_COMBINED', round_mode='HALF_TO_EVEN', narrow_range=False, axis=-100, ensure_minimum_range=10) return data test() ``` This occurs whenever `axis` is a negative value less than `-1`. In this case, we are accessing data before the start of a heap buffer: ```cc int axis = -1; Status s = c->GetAttr("axis", &axis); if (!s.ok() && s.code() != error::NOT_FOUND) { return s; } ... if (axis != -1) { ... TF_RETURN_IF_ERROR( c->Merge(c->Dim(minmax, 0), c->Dim(input, axis), &depth)); } ``` The code allows `axis` to be an optional argument (`s` would contain an `error::NOT_FOUND` error code). Otherwise, it assumes that `axis` is a valid index into the dimensions of the `input` tensor. If `axis` is less than `-1` t...
Affected versions
| Package | Affected | Fixed in |
|---|---|---|
| tensorflow PyPI | >= 2.6.0, < 2.6.1 | 2.6.1 |
Details and references
### Impact The [shape inference code for `QuantizeV2`](https://github.com/tensorflow/tensorflow/blob/8d72537c6abf5a44103b57b9c2e22c14f5f49698/tensorflow/core/framework/common_shape_fns.cc#L2509-L2530) can trigger a read outside of bounds of heap allocated array: ```python import tensorflow as tf @tf.function def test(): data=tf.raw_ops.QuantizeV2( input=[1.0,1.0], min_range=[1.0,10.0], max_range=[1.0,10.0], T=tf.qint32, mode='MIN_COMBINED', round_mode='HALF_TO_EVEN', narrow_range=False, axis=-100, ensure_minimum_range=10) return data test() ``` This occurs whenever `axis` is a negative value less than `-1`. In this case, we are accessing data before the start of a heap buffer: ```cc int axis = -1; Status s = c->GetAttr("axis", &axis); if (!s.ok() && s.code() != error::NOT_FOUND) { return s; } ... if (axis != -1) { ... TF_RETURN_IF_ERROR( c->Merge(c->Dim(minmax, 0), c->Dim(input, axis), &depth)); } ``` The code allows `axis` to be an optional argument (`s` would contain an `error::NOT_FOUND` error code). Otherwise, it assumes that `axis` is a valid index into the dimensions of the `input` tensor. If `axis` is less than `-1` then this results in a heap OOB read. ### Patches We have patched the issue in GitHub commit [a0d64445116c43cf46a5666bd4eee28e7a82f244](https://github.com/tensorflow/tensorflow/commit/a0d64445116c43cf46a5666bd4eee28e7a82f244). The fix will be included in TensorFlow 2.7.0. We will also cherrypick this commit on TensorFlow 2.6.1, as this version is the only one that is also affected. ### 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:N/A:H
- Severity from
- GitHub (reviewed advisory)
- Weakness
- CWE-125
- Also known as
- BIT-tensorflow-2021-41211, CVE-2021-41211, PYSEC-2021-403, PYSEC-2021-620, PYSEC-2021-818
- github.com/tensorflow/tensorflow/security/advisories/GHSA-cvgx-3v3q-m36c
- nvd.nist.gov/vuln/detail/CVE-2021-41211
- github.com/tensorflow/tensorflow/commit/a0d64445116c43cf46a5666bd4eee28e7a82f244
- github.com/pypa/advisory-database/tree/main/vulns/tensorflow-cpu/PYSEC-2021-620.yaml
- github.com/pypa/advisory-database/tree/main/vulns/tensorflow-gpu/PYSEC-2021-818.yaml
- github.com/pypa/advisory-database/tree/main/vulns/tensorflow/PYSEC-2021-403.yaml
- github.com/tensorflow/tensorflow
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