CVE-2021-39520: Null Pointer Dereference

Published Sep 20, 2021
·
Updated

An issue was discovered in libjpeg through 2020021. A NULL pointer dereference exists in the function BlockBitmapRequester::PushReconstructedData() located in blockbitmaprequester.cpp. It allows an attacker to cause Denial of Service.

Affected Software

1 affected component
jpeg libjpeg<=2020021

Event History

Sep 20, 2021
CVE Published
via MITRE·03:26 PM
Data Sourced
via MITRE·03:26 PM
Description
Data Sourced
via NVD·04:15 PM
RemedyDescriptionSeverityWeaknessAffected Software
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Frequently Asked Questions

1

What is CVE-2021-39520?

CVE-2021-39520 is a vulnerability found in libjpeg, specifically in the function BlockBitmapRequester::PushReconstructedData() located in blockbitmaprequester.cpp, that allows an attacker to cause a Denial of Service (DoS) by exploiting a NULL pointer dereference.

2

What is the severity of CVE-2021-39520?

CVE-2021-39520 has a severity rating of 6.5 (medium).

3

Which software is affected by CVE-2021-39520?

The vulnerability affects libjpeg with version up to and including 2020021.

4

How can an attacker exploit CVE-2021-39520?

An attacker can exploit CVE-2021-39520 by triggering a NULL pointer dereference in the BlockBitmapRequester::PushReconstructedData() function in libjpeg, leading to a Denial of Service (DoS) condition.

5

Is there a fix available for CVE-2021-39520?

At the moment, there is no known fix or patch available for CVE-2021-39520. It is recommended to stay updated with the latest security advisories and patches from the vendor.

Contact

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