CVE-2021-21017: Acrobat Reader DC Heap-based Buffer Overflow Vulnerability Could Lead To Arbitrary Code Execution

Published Feb 11, 2021
·
Updated

Acrobat Reader DC versions versions 2020.013.20074 (and earlier), 2020.001.30018 (and earlier) and 2017.011.30188 (and earlier) are affected by a heap-based buffer overflow vulnerability. An unauthenticated attacker could leverage this vulnerability to achieve arbitrary code execution in the context of the current user. Exploitation of this issue requires user interaction in that a victim must open a malicious file.

Other sources

Acrobat Acrobat and Reader contain a heap-based buffer overflow vulnerability that could allow an unauthenticated attacker to achieve code execution in the context of the current user.

CISA

Affected Software

17 affected components
Adobe Acrobat and Reader
All of the following
Any of the following
Adobe Acrobat>=17.0<=17.011.30188
Adobe Acrobat>=20.0<=20.001.30018
Adobe Acrobat DC<=20.013.20074
Adobe Acrobat reader>=17.0<=17.011.30188
Adobe Acrobat reader>=20.0<=20.001.300183
Adobe Acrobat Reader DC<=20.013.20074
Any of the following
Apple macOS
Microsoft Windows
Adobe Acrobat>=17.0<=17.011.30188
Adobe Acrobat>=20.0<=20.001.30018
Adobe Acrobat DC<=20.013.20074
Adobe Acrobat reader>=17.0<=17.011.30188
Adobe Acrobat reader>=20.0<=20.001.300183
Adobe Acrobat Reader DC<=20.013.20074
Apple macOS
Microsoft Windows

Remediation

Recommended actions to resolve this vulnerability, in priority order.

  1. Compensating control

    Prevent delivery or direct opening of potentially malicious PDF files: configure your email gateway/secure web gateway to block, quarantine, or sandbox PDF attachments from external or untrusted senders and enable attachment disarm/sandboxing for PDFs. Additionally, apply endpoint controls to restrict automatic opening of downloaded PDF files.

  2. Operational

    Warn and train users not to open unexpected or untrusted PDF files or links. Note: exploitation requires user interaction (victim opening a malicious file), so instruct users to verify sender and scan attachments before opening.

Event History

Feb 11, 2021
CVE Published
via MITRE·07:42 PM
Data Sourced
via MITRE·07:42 PM
DescriptionSeverityWeakness
Data Sourced
via NVD·08:15 PM
DescriptionSeverityWeaknessAffected Software
Nov 3, 2021
Known Exploited
via CISA·12:00 AM
Free Weekly Intel

Don't miss critical vulnerabilities

Join thousands of security professionals who receive our weekly digest of trending CVEs, zero-days, and exploited vulnerabilities.

No spam. Unsubscribe anytime.

Frequently Asked Questions

1

What is the vulnerability ID for this Adobe Acrobat and Reader vulnerability?

The vulnerability ID for this Adobe Acrobat and Reader vulnerability is CVE-2021-21017.

2

Which versions of Adobe Acrobat and Reader are affected by this vulnerability?

Acrobat Reader DC versions 2020.013.20074 (and earlier), 2020.001.30018 (and earlier), and 2017.011.30188 (and earlier) are affected by this vulnerability.

3

What is the severity rating of CVE-2021-21017?

The severity rating of CVE-2021-21017 is 8.8 (high).

4

How can an attacker exploit this vulnerability?

An unauthenticated attacker could leverage this vulnerability to achieve arbitrary code execution in the context of the current user.

5

Where can I find more information about this vulnerability?

You can find more information about this vulnerability at the following link: [Adobe Security Bulletin APSB21-09](https://helpx.adobe.com/security/products/acrobat/apsb21-09.html).

Contact

SecAlerts Pty Ltd.
132 Wickham Terrace
Fortitude Valley,
QLD 4006, Australia
info@secalerts.co
By using SecAlerts services, you agree to our services end-user license agreement. This website is safeguarded by reCAPTCHA and governed by the Google Privacy Policy and Terms of Service. All names, logos, and brands of products are owned by their respective owners, and any usage of these names, logos, and brands for identification purposes only does not imply endorsement. If you possess any content that requires removal, please get in touch with us.
© 2026 SecAlerts Pty Ltd.
ABN: 70 645 966 203, ACN: 645 966 203