5.5
MEDIUM
CVE-2021-29550
TensorFlow FractionalAvgPool Denial of Service
Description

TensorFlow is an end-to-end open source platform for machine learning. An attacker can cause a runtime division by zero error and denial of service in `tf.raw_ops.FractionalAvgPool`. This is because the implementation(https://github.com/tensorflow/tensorflow/blob/acc8ee69f5f46f92a3f1f11230f49c6ac266f10c/tensorflow/core/kernels/fractional_avg_pool_op.cc#L85-L89) computes a divisor quantity by dividing two user controlled values. The user controls the values of `input_size[i]` and `pooling_ratio_[i]` (via the `value.shape()` and `pooling_ratio` arguments). If the value in `input_size[i]` is smaller than the `pooling_ratio_[i]`, then the floor operation results in `output_size[i]` being 0. The `DCHECK_GT` line is a no-op outside of debug mode, so in released versions of TF this does not trigger. Later, these computed values are used as arguments(https://github.com/tensorflow/tensorflow/blob/acc8ee69f5f46f92a3f1f11230f49c6ac266f10c/tensorflow/core/kernels/fractional_avg_pool_op.cc#L96-L99) to `GeneratePoolingSequence`(https://github.com/tensorflow/tensorflow/blob/acc8ee69f5f46f92a3f1f11230f49c6ac266f10c/tensorflow/core/kernels/fractional_pool_common.cc#L100-L108). There, the first computation is a division in a modulo operation. Since `output_length` can be 0, this results in runtime crashing. 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.

INFO

Published Date :

May 14, 2021, 8:15 p.m.

Last Modified :

July 27, 2021, 5:19 p.m.

Remotely Exploitable :

No

Impact Score :

3.6

Exploitability Score :

1.8
Affected Products

The following products are affected by CVE-2021-29550 vulnerability. Even if cvefeed.io is aware of the exact versions of the products that are affected, the information is not represented in the table below.

ID Vendor Product Action
1 Google tensorflow
References to Advisories, Solutions, and Tools

Here, you will find a curated list of external links that provide in-depth information, practical solutions, and valuable tools related to CVE-2021-29550.

URL Resource
https://github.com/tensorflow/tensorflow/commit/548b5eaf23685d86f722233d8fbc21d0a4aecb96 Patch Third Party Advisory
https://github.com/tensorflow/tensorflow/security/advisories/GHSA-f78g-q7r4-9wcv Exploit Patch Third Party Advisory

We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).

Results are limited to the first 15 repositories due to potential performance issues.

The following list is the news that have been mention CVE-2021-29550 vulnerability anywhere in the article.

The following table lists the changes that have been made to the CVE-2021-29550 vulnerability over time.

Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.

  • CVE Modified by [email protected]

    May. 14, 2024

    Action Type Old Value New Value
  • Reanalysis by [email protected]

    Jul. 27, 2021

    Action Type Old Value New Value
    Changed CPE Configuration OR *cpe:2.3:a:google:tensorflow:*:*:*:*:*:*:*:* versions up to (including) 2.1.4 *cpe:2.3:a:google:tensorflow:*:*:*:*:*:*:*:* versions from (including) 2.2.0 up to (including) 2.2.3 *cpe:2.3:a:google:tensorflow:*:*:*:*:*:*:*:* versions from (including) 2.3.0 up to (including) 2.3.3 *cpe:2.3:a:google:tensorflow:*:*:*:*:*:*:*:* versions from (including) 2.4.0 up to (including) 2.4.2 OR *cpe:2.3:a:google:tensorflow:*:*:*:*:*:*:*:* versions up to (excluding) 2.1.4 *cpe:2.3:a:google:tensorflow:*:*:*:*:*:*:*:* versions from (including) 2.2.0 up to (excluding) 2.2.3 *cpe:2.3:a:google:tensorflow:*:*:*:*:*:*:*:* versions from (including) 2.3.0 up to (excluding) 2.3.3 *cpe:2.3:a:google:tensorflow:*:*:*:*:*:*:*:* versions from (including) 2.4.0 up to (excluding) 2.4.2
  • Initial Analysis by [email protected]

    May. 18, 2021

    Action Type Old Value New Value
    Added CVSS V2 NIST (AV:L/AC:L/Au:N/C:N/I:N/A:P)
    Added CVSS V3.1 NIST AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
    Changed Reference Type https://github.com/tensorflow/tensorflow/commit/548b5eaf23685d86f722233d8fbc21d0a4aecb96 No Types Assigned https://github.com/tensorflow/tensorflow/commit/548b5eaf23685d86f722233d8fbc21d0a4aecb96 Patch, Third Party Advisory
    Changed Reference Type https://github.com/tensorflow/tensorflow/security/advisories/GHSA-f78g-q7r4-9wcv No Types Assigned https://github.com/tensorflow/tensorflow/security/advisories/GHSA-f78g-q7r4-9wcv Exploit, Patch, Third Party Advisory
    Added CPE Configuration OR *cpe:2.3:a:google:tensorflow:*:*:*:*:*:*:*:* versions up to (including) 2.1.4 *cpe:2.3:a:google:tensorflow:*:*:*:*:*:*:*:* versions from (including) 2.2.0 up to (including) 2.2.3 *cpe:2.3:a:google:tensorflow:*:*:*:*:*:*:*:* versions from (including) 2.3.0 up to (including) 2.3.3 *cpe:2.3:a:google:tensorflow:*:*:*:*:*:*:*:* versions from (including) 2.4.0 up to (including) 2.4.2
EPSS is a daily estimate of the probability of exploitation activity being observed over the next 30 days. Following chart shows the EPSS score history of the vulnerability.
CWE - Common Weakness Enumeration

While CVE identifies specific instances of vulnerabilities, CWE categorizes the common flaws or weaknesses that can lead to vulnerabilities. CVE-2021-29550 is associated with the following CWEs:

Common Attack Pattern Enumeration and Classification (CAPEC)

Common Attack Pattern Enumeration and Classification (CAPEC) stores attack patterns, which are descriptions of the common attributes and approaches employed by adversaries to exploit the CVE-2021-29550 weaknesses.

Exploit Prediction

EPSS is a daily estimate of the probability of exploitation activity being observed over the next 30 days.

0.04 }} 0.00%

score

0.10669

percentile

CVSS31 - Vulnerability Scoring System
Attack Vector
Attack Complexity
Privileges Required
User Interaction
Scope
Confidentiality
Integrity
Availability