CVE-2021-39850: Adobe Acrobat Reader DC Null Pointer Dereference Could Lead To Application Denial-of-Service

Published Sep 29, 2021
·
Updated

Acrobat Reader DC versions 2021.005.20060 (and earlier), 2020.004.30006 (and earlier) and 2017.011.30199 (and earlier) are affected by a Null pointer dereference vulnerability. An unauthenticated attacker could leverage this vulnerability to achieve an application denial-of-service in the context of the current user. Exploitation of this issue requires user interaction in that a victim must open a malicious file.

Affected Software

24 affected components
Adobe Acrobat>=20.001.30005<=20.004.30006
Adobe Acrobat Reader>=20.001.30005<=20.004.30006
Apple macOS
Microsoft Windows
Adobe Acrobat DC>=15.008.20082<=21.005.20058
Adobe Acrobat Reader DC>=15.008.20082<=21.005.20058
Adobe Acrobat DC>=15.008.20082<=21.005.20060
Adobe Acrobat Reader DC>=15.008.20082<=21.005.20060
Adobe Acrobat>=17.011.30059<=17.011.30199
Adobe Acrobat Reader>=17.011.30059<=17.011.30199
All of the following
Any of the following
Adobe Acrobat>=20.001.30005<=20.004.30006
Adobe Acrobat Reader>=20.001.30005<=20.004.30006
Any of the following
Apple macOS
Microsoft Windows
All of the following
Any of the following
Adobe Acrobat DC>=15.008.20082<=21.005.20058
Adobe Acrobat Reader DC>=15.008.20082<=21.005.20058
Apple macOS
All of the following
Any of the following
Adobe Acrobat DC>=15.008.20082<=21.005.20060
Adobe Acrobat Reader DC>=15.008.20082<=21.005.20060
Microsoft Windows
All of the following
Any of the following
Adobe Acrobat>=17.011.30059<=17.011.30199
Adobe Acrobat Reader>=17.011.30059<=17.011.30199
Any of the following
Apple macOS
Microsoft Windows

Remediation

Recommended actions to resolve this vulnerability, in priority order.

  1. Upgrade

    Upgrade Adobe Acrobat Reader DC to a version that resolves this vulnerability.

    Fixed in 2021.005.20060
  2. Upgrade

    Upgrade Adobe Acrobat Reader DC to a version that resolves this vulnerability.

    Fixed in 2020.004.30006
  3. Upgrade

    Upgrade Adobe Acrobat Reader DC to a version that resolves this vulnerability.

    Fixed in 2017.011.30199

Event History

Sep 29, 2021
CVE Published
via MITRE·03:38 PM
Data Sourced
via MITRE·03:38 PM
DescriptionSeverityWeakness
Data Sourced
via NVD·04:15 PM
DescriptionSeverityWeaknessAffected Software

Frequently Asked Questions

1

What is the vulnerability ID of this issue?

The vulnerability ID is CVE-2021-39850.

2

What is the severity level of CVE-2021-39850?

The severity level of CVE-2021-39850 is medium.

3

Which software versions are affected by CVE-2021-39850?

Acrobat Reader DC versions 2021.005.20060 (and earlier), 2020.004.30006 (and earlier), and 2017.011.30199 (and earlier) are affected by CVE-2021-39850.

4

How can an attacker exploit CVE-2021-39850?

An unauthenticated attacker could exploit CVE-2021-39850 to achieve an application denial-of-service in the context of the affected software.

5

Where can I find more information about CVE-2021-39850?

You can find more information about CVE-2021-39850 at the following link: [Adobe Security Bulletin APSB21-55](https://helpx.adobe.com/security/products/acrobat/apsb21-55.html).

Contact

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