CVE-2023-36413 is a security feature bypass vulnerability identified in Microsoft Office 2019, specifically version 19.0.0. This vulnerability allows an attacker to circumvent certain built-in security mechanisms designed to protect users from malicious content. The vulnerability does not directly compromise confidentiality or availability but poses a high risk to integrity, meaning an attacker could potentially manipulate or execute unauthorized actions within the Office environment. The attack vector is network-based, requiring no privileges but necessitating user interaction, such as opening a crafted malicious Office document. The CVSS 3.1 base score is 6.5, indicating a medium severity level. The vulnerability was publicly disclosed on November 14, 2023, with no known exploits in the wild at the time of publication. The absence of patches at the time suggests that organizations must be vigilant and prepare to deploy updates once available. The bypass could facilitate further attacks, such as code execution or privilege escalation, by undermining security features like Protected View or macro restrictions. This vulnerability highlights the importance of layered defenses in Office environments, including user training and endpoint security controls.

For European organizations, the impact of CVE-2023-36413 could be significant, especially in sectors heavily reliant on Microsoft Office 2019 for document processing and collaboration. The integrity compromise could allow attackers to alter documents or execute unauthorized actions, potentially leading to data manipulation, fraud, or the spread of malware. Critical infrastructure, government agencies, financial institutions, and large enterprises are particularly at risk due to their reliance on Office and the sensitive nature of their data. Although confidentiality and availability are not directly impacted, the integrity breach could undermine trust in document authenticity and disrupt business processes. The requirement for user interaction means phishing or social engineering campaigns could be used to exploit this vulnerability, increasing the risk of targeted attacks. The lack of known exploits currently reduces immediate risk but does not eliminate the threat, as attackers often develop exploits after public disclosure.

1. Monitor Microsoft’s official channels and deploy security patches for Microsoft Office 2019 version 19.0.0 as soon as they become available. 2. Implement strict macro policies by disabling macros by default and only allowing signed macros from trusted sources. 3. Configure Office applications to open documents in Protected View to limit the execution of potentially malicious content. 4. Enhance email filtering and phishing detection to reduce the likelihood of malicious documents reaching end users. 5. Conduct user awareness training focused on recognizing suspicious documents and avoiding unsafe interactions. 6. Utilize endpoint detection and response (EDR) tools to monitor for anomalous Office behaviors indicative of exploitation attempts. 7. Restrict network access and apply application control policies to limit the execution of unauthorized code within Office environments. 8. Regularly audit and review Office security configurations to ensure compliance with best practices.