AI and data stack advisories

Severe, 6 weeks1498Projects326

1498 severe, 6 weeks · 326 projects

TensorFlowGHSA-4p4p-www8-8fv9

Reference binding to null in `ParameterizedTruncatedNormal`

TensorFlow

CVE-2021-29568 · Published May 21, 2021 · updated Jul 8, 2026

Low2.5
Fix: upgrade to 2.1.4 or later (4 fixed versions below)
GitHub advisory

Impact

An attacker can trigger undefined behavior by binding to null pointer in tf.raw_ops.ParameterizedTruncatedNormal:

```python

import tensorflow as tf

shape = tf.constant([], shape=[0], dtype=tf.int32)

means = tf.constant((1), dtype=tf.float32)

stdevs = tf.constant((1), dtype=tf.float32)

minvals = tf.constant((1), dtype=tf.float32)

maxvals = tf.constant((1), dtype=tf.float32)

tf.raw_ops.ParameterizedTruncatedNormal(

shape=shape, means=means, stdevs=stdevs, minvals=minvals, maxvals=maxvals)

`

This is because the [implementation](https://github.com/tensorflow/tensorflow/blob/3f6fe4dfef6f57e768260b48166c27d148f3015f/tensorflow/core/kernels/parameterized_truncated_normal_op.cc#L630) does not validate input arguments before accessing the first element of shape:

```cc

int32 num_batches = shape_tensor.flat<int32>()(0);

`

If shape argument is empty, then shape_tensor.flat<T>() is an empty array.

Patches

We have patched the issue in GitHub commit [5e52ef5a461570cfb68f3bdbbebfe972cb4e0fd8](https://github.com/tensorflow/tensorflow/commit/5e52ef5a461570cfb68f3bdbbebfe972cb4e0fd8).

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...

Affected versions

PackageAffectedFixed in
tensorflow
PyPI
< 2.1.42.1.4
>= 2.2.0, < 2.2.32.2.3
>= 2.3.0, < 2.3.32.3.3
>= 2.4.0, < 2.4.22.4.2
Details and references

### Impact An attacker can trigger undefined behavior by binding to null pointer in `tf.raw_ops.ParameterizedTruncatedNormal`: ```python import tensorflow as tf shape = tf.constant([], shape=[0], dtype=tf.int32) means = tf.constant((1), dtype=tf.float32) stdevs = tf.constant((1), dtype=tf.float32) minvals = tf.constant((1), dtype=tf.float32) maxvals = tf.constant((1), dtype=tf.float32) tf.raw_ops.ParameterizedTruncatedNormal( shape=shape, means=means, stdevs=stdevs, minvals=minvals, maxvals=maxvals) ``` This is because the [implementation](https://github.com/tensorflow/tensorflow/blob/3f6fe4dfef6f57e768260b48166c27d148f3015f/tensorflow/core/kernels/parameterized_truncated_normal_op.cc#L630) does not validate input arguments before accessing the first element of `shape`: ```cc int32 num_batches = shape_tensor.flat<int32>()(0); ``` If `shape` argument is empty, then `shape_tensor.flat<T>()` is an empty array. ### Patches We have patched the issue in GitHub commit [5e52ef5a461570cfb68f3bdbbebfe972cb4e0fd8](https://github.com/tensorflow/tensorflow/commit/5e52ef5a461570cfb68f3bdbbebfe972cb4e0fd8). 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 Ying Wang and Yakun Zhang of Baidu X-Team.

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-476, CWE-824
Also known as
BIT-tensorflow-2021-29568, CVE-2021-29568, PYSEC-2021-205, PYSEC-2021-496, PYSEC-2021-694

More TensorFlow advisories

All TensorFlow