CVE-2025-29800 is a high-severity vulnerability in Microsoft AutoUpdate (MAU) for Mac, identified as an improper privilege management issue (CWE-269). The flaw allows an authorized local attacker to elevate their privileges on the affected system. Specifically, the vulnerability arises because MAU does not correctly enforce privilege boundaries, enabling a user with limited privileges to gain higher-level access, potentially up to administrative or root level. The CVSS 3.1 base score of 7.8 reflects the significant impact on confidentiality, integrity, and availability, with a low attack complexity and no user interaction required. The attack vector is local, meaning the attacker must already have some level of access to the Mac system, but from there, they can exploit the improper privilege management to execute unauthorized actions with elevated rights. This could include installing persistent malware, modifying system configurations, or accessing sensitive data. Although no known exploits are currently reported in the wild, the vulnerability's nature and impact make it a critical concern for organizations relying on Microsoft AutoUpdate on Mac devices. The absence of published patches at this time necessitates immediate attention to mitigation strategies to reduce risk exposure.

For European organizations, this vulnerability poses a significant risk, especially those with Mac environments managed via Microsoft AutoUpdate. Successful exploitation could lead to full system compromise, data breaches, and disruption of business operations. Elevated privileges could allow attackers to bypass security controls, install persistent threats, or exfiltrate sensitive corporate or personal data. This is particularly concerning for sectors with stringent data protection requirements under GDPR, such as finance, healthcare, and government agencies. The local attack vector means that insider threats or attackers who have gained initial footholds through other means could leverage this vulnerability to escalate privileges and deepen their access. The potential impact extends to the integrity of software update mechanisms, which are critical for maintaining system security. Compromise of the update process could facilitate supply chain attacks or widespread malware distribution within an organization.

Given the lack of an official patch at this time, European organizations should implement several targeted mitigation measures: 1) Restrict local user privileges strictly, ensuring that only trusted personnel have access to accounts capable of running Microsoft AutoUpdate. 2) Employ endpoint detection and response (EDR) solutions to monitor for unusual privilege escalation behaviors or unauthorized modifications to MAU components. 3) Harden Mac systems by disabling or limiting automatic update features where feasible, or by controlling update execution through centralized management tools. 4) Conduct regular audits of user permissions and system logs to detect early signs of exploitation attempts. 5) Educate users about the risks of local privilege escalation and enforce strong access controls and physical security to prevent unauthorized local access. 6) Prepare for rapid deployment of patches once released by Microsoft by maintaining an up-to-date asset inventory and patch management process focused on Mac environments.