#VU50463 Input validation error in Microsoft products - CVE-2021-24070

Vulnerability identifier: #VU50463

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-2021-24070

CWE-ID: CWE-20

Exploitation vector: Network

Exploit availability: No

Vulnerable software:
Microsoft Office Web Apps Server
Server applications / Application servers
Office Online Server
Server applications / Other server solutions
Microsoft Office
Client/Desktop applications / Office applications
Microsoft Excel
Client/Desktop applications / Office applications

Vendor: Microsoft

Description

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

The vulnerability exists due to insufficient validation of user-supplied input in Microsoft Excel. A remote attacker can host a website, trick a victim to open the specially crafted file and execute arbitrary code on the target system.

Mitigation
Install updates from vendor's website.

Vulnerable software versions

Microsoft Office Web Apps Server: 2013 Service Pack 1

Office Online Server : 2016

Microsoft Office: 2019

Microsoft Excel: 2010, 2013 RT Service Pack 1, 2013, 2016

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External links
https://portal.msrc.microsoft.com/en-US/security-guidance/advisory/CVE-2021-24070

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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.