CVE-2021-27057: 
vulnerability analysis and mitigation

Microsoft Office Remote Code Execution Vulnerability (CVE-2021-27057) was disclosed on March 9, 2021. The vulnerability affects various Microsoft Office products including Microsoft 365 Apps Enterprise, Excel 2010-2016, and Office 2010-2016. This vulnerability is distinct from CVE-2021-24108 and CVE-2021-27059 (MITRE CVE).

The vulnerability exists within the Graph COM object and stems from improper initialization of memory prior to accessing it. It has been assigned a CVSS v3.1 base score of 7.8 (HIGH) with the vector string CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H. The vulnerability requires local access and user interaction for successful exploitation (ZDI Advisory).

If successfully exploited, this vulnerability allows attackers to execute arbitrary code in the context of the current process. The high CVSS score indicates potential severe impacts on confidentiality, integrity, and availability of the affected systems (ZDI Advisory).

The vulnerability requires user interaction to be exploited, specifically the target must visit a malicious page or open a malicious file. The attack complexity is considered low, requiring no privileges for execution (ZDI Advisory).

Microsoft has released security updates to address this vulnerability. The fix was included in the March 2021 security updates. Organizations running Office Online Server can apply security update KB4493229 to remediate this vulnerability (Microsoft Support).