CVE-2023-42860 is a vulnerability identified in Apple macOS that stems from a permissions issue allowing an application to modify protected parts of the file system. The flaw is categorized under CWE-863, which relates to improper authorization. The vulnerability affects multiple macOS versions prior to the patched releases: Sonoma 14.1, Monterey 12.7.1, and Ventura 13.6.1. Exploitation requires only local access (AV:L), with low attack complexity (AC:L), no privileges required (PR:N), and no user interaction (UI:N). The scope is unchanged (S:U), but the impact on confidentiality and integrity is high (C:H/I:H), with no impact on availability (A:N). This means an attacker with local access could potentially alter sensitive system files or configurations, compromising system integrity and confidentiality without alerting the user. Apple mitigated this by adding additional restrictions to the file system permissions model, preventing unauthorized modifications by apps. Although no exploits have been reported in the wild, the vulnerability poses a significant risk if leveraged by malicious actors or malware. The vulnerability's technical details emphasize the need for strict enforcement of file system access controls and highlight the risks of insufficient authorization checks in operating system components.

For European organizations, this vulnerability could lead to unauthorized modification of critical system files on macOS devices, potentially enabling privilege escalation, persistence of malware, or disruption of security controls. Confidential data stored on affected systems could be exposed or altered, undermining data integrity and trustworthiness of the affected endpoints. Organizations relying on macOS for sensitive operations, including government agencies, financial institutions, and technology companies, face increased risk of targeted attacks exploiting this flaw. The lack of required privileges or user interaction lowers the barrier for exploitation by insider threats or malware that gains local access. This could result in data breaches, compliance violations (e.g., GDPR), and operational disruptions. The impact is especially critical in environments where macOS devices are used for development, administration, or handling sensitive information. Failure to patch promptly could expose organizations to advanced persistent threats aiming to leverage this vulnerability for lateral movement or system compromise.

European organizations should immediately verify the macOS versions deployed across their environment and prioritize upgrading to macOS Sonoma 14.1, Monterey 12.7.1, or Ventura 13.6.1, where the vulnerability is fixed. Beyond patching, organizations should implement strict application whitelisting and limit the installation of untrusted or unnecessary software to reduce the attack surface. Employ endpoint detection and response (EDR) solutions capable of monitoring unauthorized file system modifications and suspicious local activity. Regularly audit file system permissions and application entitlements to ensure no excessive privileges are granted. Enforce least privilege principles for user accounts and applications, restricting local access where possible. Conduct user training to recognize potential insider threats and suspicious behavior. For highly sensitive environments, consider deploying macOS security features such as System Integrity Protection (SIP) and Full Disk Encryption (FileVault) to further protect system files and data confidentiality. Maintain up-to-date backups to enable recovery in case of compromise.