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GHSA-jhq9-wm9m-cf89

LowCVSS 2.5 / 10
Published May 21, 2021·Last modified Mar 13, 2026
Affected Components(0)

No affected components available

Description

Impact

An attacker can cause a denial of service by controlling the values of num_segments tensor argument for UnsortedSegmentJoin:

import tensorflow as tf

inputs = tf.constant([], dtype=tf.string)
segment_ids = tf.constant([], dtype=tf.int32)
num_segments = tf.constant([], dtype=tf.int32)
separator = ''

tf.raw_ops.UnsortedSegmentJoin(
  inputs=inputs, segment_ids=segment_ids,
  num_segments=num_segments, separator=separator)

This is because the implementation assumes that the num_segments tensor is a valid scalar:

const Tensor& num_segments_tensor = context->input(2);
auto num_segments = num_segments_tensor.scalar<NUM_SEGMENTS_TYPE>()();

Since the tensor is empty the CHECK involved in .scalar<T>()() that checks that the number of elements is exactly 1 will be invalidated and this would result in process termination.

Patches

We have patched the issue in GitHub commit 704866eabe03a9aeda044ec91a8d0c83fc1ebdbe.

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 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.

Risk Scores
Base Score
2.5

The vulnerability requires local access to the device to be exploited. It is difficult for an attacker to exploit this vulnerability and may require special conditions. An attacker needs basic access or low-level privileges. No user interaction is needed for the attacker to exploit this vulnerability. The impact is confined to the system where the vulnerability exists. There is a low impact on the availability of the system.

Threat Intelligence
2.3

Limited exploitation activity has been observed. Close monitoring and planned remediation are recommended.

EPSS
0.19%

The exploit probability is very low. The vulnerability is unlikely to be exploited in the next 30 days.

Exploit
Not available

We did not find any exploit available. Neither in GitHub repositories nor in the Exploit-Database.

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Low severity
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