CVE-2021-39859

Name: CVE-2021-39859
Creator: NVD / NIST
Published: 2023-09-06T14:15:09.477+00:00
License: https://creativecommons.org/publicdomain/zero/1.0/

MEDIUMCVSS 5.5/10EPSS 0.42%

Last modified Jun 17, 2026

CVE-2021-39859 is a medium-severity vulnerability rated 5.5/10 on the CVSS scale. Acrobat Reader DC versions 2021.005.20060 (and earlier), 2020.004.30006 (and earlier) and 2017.011.30199 (and earlier) are affected by a Use After Free vulnerability that could lead to disclosure of sensitive memory. An attacker could leverage this vulnerability to bypass mitigations such as ASLR. EPSS estimates a 0.42% chance of exploitation in the next 30 days.

Description

Acrobat Reader DC versions 2021.005.20060 (and earlier), 2020.004.30006 (and earlier) and 2017.011.30199 (and earlier) are affected by a Use After Free vulnerability that could lead to disclosure of sensitive memory. An attacker could leverage this vulnerability to bypass mitigations such as ASLR. Exploitation of this issue requires user interaction in that a victim must open a malicious file.

Metrics

CVSS 3.1

5.5/10

CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:N/A:N

EPSS Probability

0.42%

33.9th percentile

Probability of exploitation in the next 30 days. Learn more

Weakness Enumeration

CWE-416

Affected Software

Vendor	Product	Versions
Adobe	Acrobat Dc	>= 15.007.20033, <= 21.005.20060
Adobe	Acrobat Reader Dc	>= 15.007.20033, <= 21.005.20060
Adobe	Acrobat Dc	>= 15.007.20033, <= 21.005.20058
Adobe	Acrobat Reader Dc	>= 15.007.20033, <= 21.005.20058
Adobe	Acrobat	>= 17.011.30180, < 17.011.30202
Adobe	Acrobat	>= 20.001.30005, < 20.004.30015
Adobe	Acrobat Reader	>= 17.011.30180, < 17.011.30202
Adobe	Acrobat Reader	>= 20.001.30005, < 20.004.30015

References

https://helpx.adobe.com/security/products/acrobat/apsb21-55.htmlVendor Advisory
https://helpx.adobe.com/security/products/acrobat/apsb21-55.htmlVendor Advisory

Timeline

Published: Sep 6, 2023
Last Modified: Jun 17, 2026
Status: Modified

Frequently Asked Questions

What is CVE-2021-39859?

How severe is CVE-2021-39859?

CVE-2021-39859 has a CVSS score of 5.5/10 (MEDIUM severity). The EPSS model estimates a 0.42% probability of exploitation in the next 30 days.

How do I fix CVE-2021-39859?

Check the vendor references and advisories linked above for patched versions and mitigation guidance. You can also run a Strix scan to test if your systems are affected.

Are you affected by CVE-2021-39859?

Run a free Strix scan to check your systems for this vulnerability.

Scan your code now

Source: NVD / NIST