CVE-2025-29801 is a high-severity vulnerability identified in Microsoft AutoUpdate (MAU) for Mac systems. The root cause is incorrect default permissions configured within the MAU application, classified under CWE-276 (Incorrect Default Permissions). This misconfiguration allows an authorized local attacker—someone with limited privileges on the affected Mac system—to escalate their privileges. Specifically, the vulnerability enables the attacker to gain higher-level access rights than intended, potentially leading to full system compromise. The CVSS 3.1 base score of 7.8 reflects the significant impact on confidentiality, integrity, and availability, with a vector indicating local attack vector (AV:L), low attack complexity (AC:L), requiring low privileges (PR:L), and no user interaction (UI:N). The scope is unchanged (S:U), but the impact on confidentiality, integrity, and availability is high (C:H/I:H/A:H). Although no known exploits are currently reported in the wild, the vulnerability poses a substantial risk due to the nature of privilege escalation on Mac endpoints, which are often used in enterprise environments. The lack of a patch link suggests that remediation may not yet be publicly available, emphasizing the need for immediate mitigation efforts. This vulnerability is particularly critical because Microsoft AutoUpdate is widely used to keep Microsoft Office and related applications up to date on Mac devices, making it a common component in many organizational environments.

For European organizations, this vulnerability presents a significant threat to endpoint security, particularly in environments with a substantial Mac user base. Successful exploitation could allow attackers to elevate privileges from a standard user to an administrative level, enabling them to install malware, exfiltrate sensitive data, or disrupt operations. This could lead to breaches of personal data protected under GDPR, resulting in regulatory penalties and reputational damage. The high impact on confidentiality, integrity, and availability means that critical business applications and data could be compromised. Additionally, since Microsoft Office products are widely used across European enterprises, the risk of lateral movement within networks increases if attackers gain elevated access on individual Mac endpoints. The absence of known exploits in the wild currently provides a window for proactive defense, but organizations should not delay in addressing this vulnerability due to its high severity and potential for exploitation.

European organizations should implement the following specific mitigation strategies: 1) Immediately audit and restrict permissions on Microsoft AutoUpdate directories and executables to ensure they follow the principle of least privilege, preventing unauthorized modification or execution. 2) Employ endpoint detection and response (EDR) tools to monitor for unusual privilege escalation attempts on Mac devices. 3) Enforce strict user account controls, limiting the number of users with local administrative privileges to reduce the attack surface. 4) Apply network segmentation to isolate Mac endpoints from critical infrastructure where feasible. 5) Monitor vendor communications closely for official patches or updates from Microsoft and prioritize their deployment once available. 6) Educate IT staff and users about the risks of local privilege escalation vulnerabilities and encourage reporting of suspicious system behavior. 7) Consider temporary compensating controls such as disabling automatic updates or restricting MAU execution via application whitelisting until a patch is released.