Vulnerability identifier: #VU52143

Vulnerability risk: High

CVSSv3.1: 7.7 [CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H/E:U/RL:O/RC:C]

CVE-ID: CVE-2021-28453

CWE-ID: CWE-94

Exploitation vector: Network

Exploit availability: No

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

Vendor: Microsoft

Description

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

The vulnerability exists due to improper input validation in Microsoft Word. A remote attacker can send a specially crafted request 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

Microsoft SharePoint Server: 2010 - 2019

Microsoft Office: 2019 - 2019 for Mac, 2010 Service Pack 2

Office Online Server : 2016

Microsoft Word:

Microsoft Office Web Apps: 2010 Service Pack 2

Microsoft Office Web Apps Server: 2013 Service Pack 1

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External links
http://portal.msrc.microsoft.com/en-US/security-guidance/advisory/CVE-2021-28453

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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.