#VU56554 NULL pointer dereference in Adobe Acrobat and Adobe Reader - CVE-2021-39851

Vulnerability identifier: #VU56554

Vulnerability risk: Low

CVSSv4.0: 1 [CVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:A/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N/E:U/U:Clear]

CVE-ID: CVE-2021-39851

CWE-ID: CWE-476

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 perform a denial of service (DoS) attack.

The vulnerability exists due to a NULL pointer dereference error. A remote attacker can trick the victim to open a specially crafted file and perform a denial of service (DoS) attack.

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.