CVE-2025-24239 is a vulnerability identified in Apple macOS that allows an application to access protected user data improperly. The root cause is a downgrade issue related to code-signing enforcement, which previously allowed apps to bypass certain security checks. Apple addressed this by introducing additional code-signing restrictions in macOS Sequoia 15.4, effectively closing the loophole. The vulnerability is classified under CWE-200 (Exposure of Sensitive Information to an Unauthorized Actor), indicating that confidentiality is compromised. The CVSS v3.1 base score is 6.5 (medium severity), with an attack vector of network (AV:N), low attack complexity (AC:L), requiring privileges (PR:L), no user interaction (UI:N), and impacting confidentiality (C:H) but not integrity or availability. This means an attacker with limited privileges on the system could exploit the vulnerability remotely without user interaction to access sensitive user data. No public exploits or active exploitation campaigns have been reported to date. The affected versions are unspecified but presumably include macOS versions prior to Sequoia 15.4. The vulnerability highlights the importance of robust code-signing enforcement to prevent unauthorized data access by malicious or compromised applications.

For European organizations, this vulnerability poses a risk to the confidentiality of sensitive user data on macOS devices. Organizations relying on macOS for critical operations, especially those handling personal data under GDPR, could face data breaches leading to regulatory penalties and reputational damage. The ability for an app with limited privileges to access protected data without user interaction increases the risk of stealthy data exfiltration. This is particularly concerning for sectors such as finance, healthcare, and government, where sensitive information is prevalent. Although integrity and availability are not impacted, the confidentiality breach alone can have severe consequences, including loss of intellectual property and exposure of personal identifiable information (PII). The lack of known exploits reduces immediate risk but does not eliminate the threat, as attackers may develop exploits once the vulnerability details are widely known.

1. Upgrade all macOS systems to Sequoia 15.4 or later immediately to apply the patch that addresses this vulnerability. 2. Implement strict application whitelisting and vetting processes to prevent installation of untrusted or unsigned applications. 3. Employ endpoint detection and response (EDR) solutions capable of monitoring for anomalous access to protected user data. 4. Restrict user privileges to the minimum necessary to reduce the risk of privilege escalation and exploitation. 5. Conduct regular audits of installed applications and their permissions to detect unauthorized or suspicious software. 6. Educate users and administrators about the risks of installing unverified software and the importance of timely updates. 7. Monitor security advisories from Apple and related threat intelligence sources for any emerging exploit reports or additional patches.