Multiple vulnerabilities in Microsoft Excel

Published: 2021-01-12

Risk	High
Patch available	YES
Number of vulnerabilities	2
CVE ID	CVE-2021-1713 CVE-2021-1714
CWE ID	CWE-20
Exploitation vector	Network
Public exploit	N/A
Vulnerable software Subscribe	Microsoft Office Client/Desktop applications / Office applications Microsoft Excel Client/Desktop applications / Office applications Excel Services on Microsoft SharePoint Server Client/Desktop applications / Office applications Office Online Server Server applications / Other server solutions Microsoft Office Web Apps Server Server applications / Application servers Microsoft SharePoint Server Server applications / Application servers
Vendor	Microsoft

Security Advisory

1) Input validation error

Risk: High

CVSSv3: 7.7 [CVSS:3.0/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H/E:U/RL:O/RC:C] [PCI]

CVE-ID: CVE-2021-1713

CWE-ID: CWE-20 - Improper Input Validation

Exploit availability: No

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 pass specially crafted input to the application and execute arbitrary code on the target system.

Mitigation

Install updates from vendor's website.

Vulnerable software versions

Microsoft Office: 2019, 2019 for Mac

Office Online Server : 2016

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

Microsoft Office Web Apps Server: 2013 Service Pack 1

CPE

External links

https://portal.msrc.microsoft.com/en-US/security-guidance/advisory/CVE-2021-1713

Q & A

Can this vulnerability be exploited remotely?

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

How the attacker can exploit this vulnerability?

The attacker would have to trick the victim to visit a specially crafted website or open an attachment in an e-mail message.

Is there known malware, which exploits this vulnerability?

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

2) Input validation error