#VU56528 Type Confusion in Adobe Acrobat and Adobe Reader - CVE-2021-39841

Vulnerability identifier: #VU56528

Vulnerability risk: High

CVSSv4.0: 5.7 [CVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:A/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:U/U:Amber]

CVE-ID: CVE-2021-39841

CWE-ID: CWE-843

Exploitation vector: Network

Exploit availability: No

Vulnerable software:
Adobe Acrobat
Client/Desktop applications / Office applications
Adobe Reader
Client/Desktop applications / Office applications

Vendor: Adobe

Description

The vulnerability allows a remote attacker to execute arbitrary code on the target system.

The vulnerability exists due to a type confusion error when processing PDF files. A remote attacker can trick the victim to open a specially crafted PDF file, trigger a type confusion error and execute arbitrary code on the target system.

Successful exploitation of this vulnerability may result in complete compromise of vulnerable system.

Mitigation
Install updates from vendor's website.

Vulnerable software versions

Adobe Acrobat: 17.008.30051 - 17.011.30199, 20.001.30020 - 20.013.20074, 21.001.20135 - 21.005.20148

Adobe Reader: 21.001.20135, 21.001.20149, 21.001.20150, 21.001.20155, 21.005.20054, 21.005.20058, 21.005.20060, 21.005.20148, 2017.008.30051 - 2020.013.20074

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External links
https://helpx.adobe.com/security/products/acrobat/apsb21-55.html

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Q & A

Can this vulnerability be exploited remotely?

Yes. This vulnerability can be exploited by a remote non-authenticated attacker via the Internet.

Is there known malware, which exploits this vulnerability?

No. We are not aware of malware exploiting this vulnerability.