CVE-2023-36761 is a vulnerability identified in Microsoft Office 2019, specifically affecting the Word component. It is classified under CWE-20, indicating improper input validation. This flaw allows an attacker to craft malicious Word documents that, when opened by a user, can lead to unauthorized information disclosure. The vulnerability is exploitable remotely over the network without requiring any privileges or authentication, but it does require user interaction, such as opening or previewing a malicious document. The CVSS 3.1 base score is 6.5, categorized as medium severity, with a vector indicating network attack vector (AV:N), low attack complexity (AC:L), no privileges required (PR:N), user interaction required (UI:R), and high confidentiality impact (C:H) but no impact on integrity or availability. The vulnerability was published on September 12, 2023, and no known exploits have been reported in the wild to date. The root cause is improper input validation, which may allow sensitive information to be leaked from the affected system. Microsoft Office 2019 version 19.0.0 is confirmed affected, and while no patch links are currently provided, it is expected that Microsoft will release updates to address this issue. Organizations relying on Microsoft Office 2019 for document processing are advised to monitor for patches and apply them promptly once available.

The primary impact of CVE-2023-36761 is unauthorized disclosure of sensitive information from affected systems running Microsoft Office 2019. For European organizations, this could lead to leakage of confidential business data, intellectual property, or personal data protected under GDPR, potentially resulting in regulatory penalties and reputational damage. Since the vulnerability requires user interaction, phishing or social engineering campaigns could be used to deliver malicious documents, increasing the risk in sectors with high document exchange such as finance, legal, and government. The lack of impact on integrity and availability limits the threat to confidentiality only, but the ease of exploitation over the network without privileges means a wide range of users could be targeted. The absence of known exploits in the wild reduces immediate risk but does not eliminate the threat of future exploitation. Organizations with extensive use of Microsoft Office 2019, especially those with remote or hybrid workforces, may face increased exposure.

1. Monitor Microsoft security advisories closely and apply official patches or updates for Microsoft Office 2019 as soon as they are released. 2. Implement strict email filtering and attachment scanning to block or flag suspicious Word documents, especially from unknown or untrusted sources. 3. Educate users on the risks of opening unsolicited or unexpected documents and train them to recognize phishing attempts. 4. Use application control or sandboxing technologies to isolate document processing and limit potential data leakage. 5. Employ Data Loss Prevention (DLP) solutions to detect and prevent unauthorized transmission of sensitive information. 6. Disable or restrict macros and other active content in Office documents where possible to reduce attack surface. 7. Maintain up-to-date endpoint protection and network monitoring to detect anomalous behavior related to document handling. 8. Review and tighten access controls and permissions on sensitive documents to minimize exposure if a disclosure occurs.