Multiple vulnerabilities in Microsoft Office
| Risk | Critical |
| Patch available | YES |
| Number of vulnerabilities | 4 |
| CVE-ID | CVE-2021-27057 CVE-2021-24108 CVE-2021-27059 CVE-2021-27058 |
| CWE-ID | CWE-94 |
| Exploitation vector | Network |
| Public exploit | Vulnerability #3 is being exploited in the wild. |
| Vulnerable software |
Microsoft Office Client/Desktop applications / Office applications Microsoft Excel Client/Desktop applications / Office applications Microsoft Office Web Apps Client/Desktop applications / Office applications Microsoft 365 Apps for Enterprise Client/Desktop applications / Office applications Office Online Server Server applications / Other server solutions |
| Vendor | Microsoft |
Security Bulletin
This security bulletin contains information about 4 vulnerabilities.
Updated: 18.03.2021
Updated description for vulnerability #VU51333.
Updated: 19.05.2021
Added information about in-the-wild exploitatin of vulnerability #3 (#VU51335). Raised bulletin risk level from High to Critical.
1) Code Injection
EUVDB-ID: #VU51333
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-2021-27057
CWE-ID:
CWE-94 - Improper Control of Generation of Code ('Code Injection')
Exploit availability: No
DescriptionThe vulnerability allows a remote attacker to execute arbitrary code on the target system.
The vulnerability exists due to improper input validation within the Graph COM object in Microsoft Office. 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.
MitigationInstall updates from vendor's website.
Vulnerable software versionsMicrosoft Office: 2010 Service Pack 2 - 2019
Office Online Server: 2016
Microsoft Excel: 2010 - 2016
Microsoft Office Web Apps: 2013 Service Pack 1
CPE2.3- cpe:2.3:a:microsoft:microsoft_office:2010 Service Pack 2:*:*:*:*:*:*:*
- cpe:2.3:a:microsoft:microsoft_office:*:*:*:*:*:*:*:*
- cpe:2.3:a:microsoft:office_online_server:2016:*:*:*:*:*:*:*
- cpe:2.3:a:microsoft:microsoft_excel:*:*:*:*:*:microsoft_office:*:*
- cpe:2.3:a:microsoft:microsoft_excel:2013 RT Service Pack 1:*:*:*:*:microsoft_office:*:*
- cpe:2.3:a:microsoft:microsoft_office_web_apps:2013 Service Pack 1:*:*:*:*:microsoft_office:*:*
http://portal.msrc.microsoft.com/en-US/security-guidance/advisory/CVE-2021-27057
http://www.zerodayinitiative.com/advisories/ZDI-21-334/
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.
2) Code Injection
EUVDB-ID: #VU51336
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-2021-24108
CWE-ID:
CWE-94 - Improper Control of Generation of Code ('Code Injection')
Exploit availability: No
DescriptionThe vulnerability allows a remote attacker to execute arbitrary code on the target system.
The vulnerability exists due to improper input validation in Microsoft Office. 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.
MitigationInstall updates from vendor's website.
Vulnerable software versionsMicrosoft Office: 2010 Service Pack 2 - 2019
CPE2.3http://portal.msrc.microsoft.com/en-US/security-guidance/advisory/CVE-2021-24108
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.
3) Code Injection
EUVDB-ID: #VU51335
Risk: Critical
CVSSv3.1: 7.2 [CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:H/I:H/A:H/E:H/RL:O/RC:C]
CVE-ID: CVE-2021-27059
CWE-ID:
CWE-94 - Improper Control of Generation of Code ('Code Injection')
Exploit availability: No
DescriptionThe vulnerability allows a remote user to execute arbitrary code on the target system.
The vulnerability exists due to improper input validation in Microsoft Office. A remote administrator 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.
Note, the vulnerability is being actively exploited in the wild.
Install updates from vendor's website.
Vulnerable software versionsMicrosoft Office: 2010 Service Pack 2 - 2016
CPE2.3http://portal.msrc.microsoft.com/en-US/security-guidance/advisory/CVE-2021-27059
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?
Yes. This vulnerability is being exploited in the wild.
4) Code Injection
EUVDB-ID: #VU51334
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-2021-27058
CWE-ID:
CWE-94 - Improper Control of Generation of Code ('Code Injection')
Exploit availability: No
DescriptionThe vulnerability allows a remote attacker to execute arbitrary code on the target system.
The vulnerability exists due to improper input validation in Microsoft Office ClickToRun. 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.
MitigationInstall updates from vendor's website.
Vulnerable software versionsMicrosoft 365 Apps for Enterprise: 32-bit Systems - 64-bit Systems
CPE2.3- cpe:2.3:a:microsoft:microsoft_365_apps_for_enterprise:32-bit Systems:*:*:*:*:*:*:*
- cpe:2.3:a:microsoft:microsoft_365_apps_for_enterprise:64-bit Systems:*:*:*:*:*:*:*
http://portal.msrc.microsoft.com/en-US/security-guidance/advisory/CVE-2021-27058
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.
