Multiple vulnerabilities in Microsoft Excel

1) Code Injection

EUVDB-ID: #VU57262

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-2021-40485

CWE-ID: CWE-94 - Improper Control of Generation of Code ('Code Injection')

Exploit availability: No

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 Excel. A remote attacker can trick a victim to open a specially crafted file 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: 2013

Microsoft Office: 2019 - 2019 for Mac

Office Online Server : 2016

Microsoft Excel: 2013 - 2016

External links

http://portal.msrc.microsoft.com/en-US/security-guidance/advisory/CVE-2021-40485

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.

2) Information disclosure

EUVDB-ID: #VU57267

Risk: Low

CVSSv3.1: 4.8 [CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N/E:U/RL:O/RC:C]

CVE-ID: CVE-2021-40472

CWE-ID: CWE-200 - Information exposure

Exploit availability: No

Description

The vulnerability allows a local user to gain access to potentially sensitive information.

The vulnerability exists due to excessive data output by the application in Microsoft Excel. A local user can gain unauthorized access to sensitive information on the system.

Mitigation

Install updates from vendor's website.

Vulnerable software versions

Microsoft Office: 2013 - 2019

Office Online Server : 2016

Microsoft Excel: 2013 - 2016

Microsoft Office Web Apps Server: 2013 Service Pack 1

External links

http://portal.msrc.microsoft.com/en-US/security-guidance/advisory/CVE-2021-40472

Q & A

Can this vulnerability be exploited remotely?

No. This vulnerability can be exploited locally. The attacker should have authentication credentials and successfully authenticate on the system.

How the attacker can exploit this vulnerability?

The attacker would have to trick the victim to visit a specially crafted website or open a file.

The attacker would have to login to the system and perform certain actions in order to exploit this vulnerability.

Is there known malware, which exploits this vulnerability?

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

3) Code Injection

EUVDB-ID: #VU57266

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-2021-40471

CWE-ID: CWE-94 - Improper Control of Generation of Code ('Code Injection')

Exploit availability: No

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 Excel. A remote attacker can trick a victim to open a specially crafted file 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 Office: 2013 - 2019

External links

http://portal.msrc.microsoft.com/en-US/security-guidance/advisory/CVE-2021-40471

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 a file.

Is there known malware, which exploits this vulnerability?

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

4) Code Injection

EUVDB-ID: #VU57265

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-2021-40473

CWE-ID: CWE-94 - Improper Control of Generation of Code ('Code Injection')

Exploit availability: No

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 Excel. A remote attacker can trick a victim to open a specially crafted file 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 Office: 2013 - 2019

External links

http://portal.msrc.microsoft.com/en-US/security-guidance/advisory/CVE-2021-40473

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 a file.

Is there known malware, which exploits this vulnerability?

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

5) Use-after-free

EUVDB-ID: #VU57264

Risk: High

CVSSv3.1: 7.9 [CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H/E:P/RL:O/RC:C]

CVE-ID: CVE-2021-40474

CWE-ID: CWE-416 - Use After Free

Exploit availability: Yes

Description

The vulnerability allows a remote attacker to compromise vulnerable system.

The vulnerability exists due to a use-after-free error when parsing Microsoft Excel files. A remote attacker can create a specially crafted Microsoft Excel file, trick the victim into opening it, trigger a use-after-free error and execute arbitrary code on the system.

Successful exploitation of the vulnerability may allow an attacker to compromise vulnerable system.

Mitigation

Install updates from vendor's website.

Vulnerable software versions

Microsoft Office: 2019 - 2019 for Mac

Office Online Server : 2016

Microsoft Excel: 2013 - 2016

Microsoft Office Web Apps Server: 2013 Service Pack 1

External links

http://portal.msrc.microsoft.com/en-US/security-guidance/advisory/CVE-2021-40474

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 a file.

Is there known malware, which exploits this vulnerability?

No. We are not aware of malware exploiting this vulnerability. However, proof of concept for this vulnerability is available.

6) Code Injection

EUVDB-ID: #VU57263

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-2021-40479

CWE-ID: CWE-94 - Improper Control of Generation of Code ('Code Injection')

Exploit availability: No

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 Excel. A remote attacker can trick a victim to open a specially crafted file 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 Office: 2013 - 2019

External links

http://portal.msrc.microsoft.com/en-US/security-guidance/advisory/CVE-2021-40479

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 a file.

Is there known malware, which exploits this vulnerability?

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