Multiple vulnerabilities in Microsoft Office Graphics
| Risk | High |
| Patch available | YES |
| Number of vulnerabilities | 2 |
| CVE-ID | CVE-2021-31940 CVE-2021-31941 |
| CWE-ID | CWE-94 CWE-416 |
| Exploitation vector | Network |
| Public exploit | N/A |
| Vulnerable software |
Microsoft Office Client/Desktop applications / Office applications Microsoft 365 Apps for Enterprise Client/Desktop applications / Office applications Microsoft Outlook Client/Desktop applications / Office applications |
| Vendor | Microsoft |
Security Bulletin
This security bulletin contains information about 2 vulnerabilities.
1) Code Injection
EUVDB-ID: #VU53887
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-2021-31940
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 Graphics. A remote attacker can trick a victim to open a specially crafted file or visit a malicious website 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: 2013 RT - 2019
Microsoft 365 Apps for Enterprise: 32-bit Systems - 64-bit Systems
CPE2.3- cpe:2.3:a:microsoft:microsoft_office:*:*:*:*:*:*:*:*
- 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:*:*:*:*:*:*:*
https://portal.msrc.microsoft.com/en-US/security-guidance/advisory/CVE-2021-31940
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) Use-after-free
EUVDB-ID: #VU53888
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-2021-31941
CWE-ID:
CWE-416 - Use After Free
Exploit availability: No
DescriptionThe vulnerability allows a remote attacker to compromise vulnerable system.
The vulnerability exists due to a use-after-free error when processing Excel files in Microsoft Office Graphics. A remote attacker can create a specially crafted 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.
MitigationInstall updates from vendor's website.
Vulnerable software versionsMicrosoft Office: 2013 RT - 2019
Microsoft Outlook: 2013 RT Service Pack 1
CPE2.3 External linkshttps://portal.msrc.microsoft.com/en-US/security-guidance/advisory/CVE-2021-31941
https://www.zerodayinitiative.com/advisories/ZDI-21-669/
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.
