CVE-2025-29792 is a use-after-free vulnerability classified under CWE-416 affecting Microsoft 365 Apps for Enterprise, specifically version 16.0.1. This vulnerability arises when the application improperly manages memory, freeing an object while it is still in use, which can lead to execution of arbitrary code or corruption of memory. An attacker with local access and limited privileges can exploit this flaw to elevate their privileges on the system, potentially gaining administrative rights. The attack requires user interaction, such as opening a malicious document or triggering a specific application behavior. The vulnerability impacts confidentiality, integrity, and availability, as an attacker could execute arbitrary code with elevated privileges, modify or exfiltrate sensitive data, or disrupt system operations. The CVSS 3.1 base score of 7.3 indicates high severity, with attack vector local (AV:L), low attack complexity (AC:L), privileges required (PR:L), and user interaction (UI:R). The scope remains unchanged (S:U), but the impact on confidentiality, integrity, and availability is high (C:H/I:H/A:H). No public exploits are known yet, and no patches have been released at the time of publication. The vulnerability was reserved on March 11, 2025, and published on April 8, 2025. Given Microsoft 365’s widespread use in enterprise environments, this vulnerability poses a significant risk if exploited.

European organizations using Microsoft 365 Apps for Enterprise version 16.0.1 face a significant risk from this vulnerability. Successful exploitation can lead to local privilege escalation, enabling attackers to gain administrative control over affected systems. This can result in unauthorized access to sensitive corporate data, disruption of business operations, and potential lateral movement within networks. Organizations in sectors with strict data protection requirements, such as finance, healthcare, and government, may suffer severe regulatory and reputational consequences. The requirement for local access and user interaction somewhat limits remote exploitation but does not eliminate risk, especially in environments with many users or shared workstations. The absence of a patch increases exposure time, necessitating immediate compensating controls. The vulnerability could also be leveraged in targeted attacks against high-value European enterprises, amplifying its impact.

1. Restrict local access to systems running Microsoft 365 Apps for Enterprise version 16.0.1 by enforcing strict physical and logical access controls. 2. Apply the principle of least privilege to limit user permissions, reducing the potential impact of privilege escalation. 3. Educate users to avoid opening suspicious or unexpected Office documents and to report unusual application behavior. 4. Monitor endpoint activity for signs of exploitation attempts, such as unusual process behavior or privilege escalations. 5. Implement application whitelisting and endpoint detection and response (EDR) solutions to detect and block malicious activity. 6. Prepare for rapid deployment of official patches once Microsoft releases them by maintaining an up-to-date asset inventory and patch management process. 7. Consider isolating critical systems or using virtualization/containerization to limit the scope of potential exploitation. 8. Regularly review and audit local administrator accounts and privileges to detect unauthorized changes.