PT-2021-4839 · Adobe · Acrobat Reader

Published 2021-09-14 · Updated 2022-02-05 · CVE-2021-39846

Positive Technologies (AI Summary)

CVSS v2.0

9.3

High

Base vector

AV:N/AC:M/Au:N/C:C/I:C/A:C

Name of the Vulnerable Software and Affected Versions Acrobat Reader DC versions 2021.005.20060 and earlier Acrobat Reader DC versions 2020.004.30006 and earlier Acrobat Reader DC versions 2017.011.30199 and earlier

Description The issue is related to a stack overflow vulnerability due to insecure handling of a crafted PDF file, potentially resulting in memory corruption in the context of the current user. Exploitation requires user interaction, where a victim must open a crafted PDF file in Acrobat Reader. This vulnerability allows attackers to execute arbitrary code.

Recommendations For Acrobat Reader DC versions 2021.005.20060 and earlier, update to a version later than 2021.005.20060 to resolve the issue. For Acrobat Reader DC versions 2020.004.30006 and earlier, update to a version later than 2020.004.30006 to resolve the issue. For Acrobat Reader DC versions 2017.011.30199 and earlier, update to a version later than 2017.011.30199 to resolve the issue. As a temporary workaround, consider avoiding the use of crafted PDF files in Acrobat Reader until a patch is available.

Fix

Stack Overflow

Memory Corruption

Weakness Enumeration

CWE-121

CWE-787

Related Identifiers

BDU:2021-05567

CVE-2021-39846

Affected Products

Acrobat Reader

References · 7

• https://osv.dev/vulnerability/CVE-2021-39846 · Vendor Advisory
• https://nvd.nist.gov/vuln/detail/CVE-2021-39846 · Security Note
• https://helpx.adobe.com/security/products/acrobat/apsb21-55.html · Vendor Advisory
• https://safe-surf.ru/specialists/bulletins-nkcki/669565 · Security Note
• https://bdu.fstec.ru/vul/2021-05567 · Security Note
• https://t.me/cibsecurity/29652 · Telegram Post
• https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2021-39846 · Note