CVE-2024-23266 is a vulnerability identified in Apple macOS that permits an application to modify protected parts of the file system due to inadequate access control enforcement (CWE-284). This flaw allows an unprivileged app, without requiring prior privileges (PR:N), but with user interaction (UI:R), to alter system files that are normally protected, thereby compromising system integrity (I:H) without affecting confidentiality (C:N) or availability (A:N). The vulnerability affects unspecified versions of macOS prior to the patched releases: Sonoma 14.4, Monterey 12.7.4, and Ventura 13.6.5. The root cause lies in insufficient validation checks that were improved in the fixed versions. Although the attack vector is local (AV:L), meaning the attacker must have local access and induce user interaction, the impact on integrity is significant as it could allow malicious apps to persist or escalate privileges indirectly by modifying critical system files. No public exploits have been reported yet, but the medium CVSS score of 5.5 reflects the moderate risk due to the required user interaction and local access. The vulnerability highlights the importance of strict access control mechanisms in protecting system files from unauthorized modifications by applications.

For European organizations, this vulnerability poses a moderate risk primarily to the integrity of macOS systems. Compromise of protected file system areas could allow attackers to implant persistent malware, alter system configurations, or bypass security controls, potentially leading to further compromise or data manipulation. While confidentiality and availability are not directly impacted, integrity breaches can undermine trust in system operations and complicate incident response. Organizations relying on macOS for critical business functions, development, or security operations could face operational disruptions or increased attack surface if exploited. The requirement for local access and user interaction limits remote exploitation but insider threats or social engineering attacks could leverage this vulnerability. Given the widespread use of Apple devices in sectors such as finance, technology, and government across Europe, unpatched systems could be targeted for lateral movement or persistence by threat actors.

European organizations should immediately deploy the macOS updates Sonoma 14.4, Monterey 12.7.4, and Ventura 13.6.5 or later to remediate this vulnerability. Beyond patching, organizations should enforce strict application control policies, limiting app installations to trusted sources such as the Apple App Store or enterprise-signed applications. Implement endpoint detection and response (EDR) solutions capable of monitoring unauthorized modifications to protected filesystem areas. User training to recognize and avoid social engineering attempts that could trigger malicious app execution is critical. Additionally, applying least privilege principles by restricting user permissions can reduce the risk of exploitation. Regularly auditing system integrity and employing file integrity monitoring tools will help detect suspicious changes early. For environments with sensitive data or critical infrastructure, consider isolating macOS systems or using virtualization to limit exposure.