CVE-2025-43396 is a logic-based vulnerability affecting Apple macOS sandboxing mechanisms, identified as CWE-284 (Improper Access Control). The sandbox is designed to isolate applications and restrict their access to system resources and user data. However, due to insufficient or flawed validation logic, a sandboxed application may bypass intended restrictions and access sensitive user data that should be protected. This vulnerability requires user interaction, such as running or installing the malicious sandboxed app, but does not require elevated privileges or prior authentication. The CVSS v3.1 score is 5.5 (medium), reflecting the local attack vector (AV:L), low attack complexity (AC:L), no privileges required (PR:N), user interaction required (UI:R), unchanged scope (S:U), high confidentiality impact (C:H), and no impact on integrity or availability (I:N/A:N). Apple has released patches in macOS Sequoia 15.7.2, Tahoe 26.1, and Sonoma 14.8.2 to improve sandbox checks and prevent unauthorized data access. No public exploits or active exploitation have been reported to date. The vulnerability primarily threatens confidentiality by potentially exposing sensitive user data to malicious sandboxed applications, which could include personal files, credentials, or other protected information.

For European organizations, this vulnerability poses a risk to the confidentiality of sensitive user data on macOS devices. Organizations with employees or systems running vulnerable macOS versions may face data leakage risks if malicious sandboxed apps are introduced, either via social engineering or supply chain compromise. The impact is particularly significant for sectors handling sensitive personal or corporate data, such as finance, healthcare, legal, and government entities. While the vulnerability does not affect system integrity or availability, unauthorized data access could lead to privacy violations, regulatory non-compliance (e.g., GDPR), reputational damage, and potential financial losses. The requirement for user interaction limits large-scale automated exploitation but does not eliminate targeted attacks. Organizations relying heavily on Apple ecosystems for endpoint devices or critical workflows are at increased risk.

1. Immediately apply the security updates released by Apple for macOS Sequoia 15.7.2, Tahoe 26.1, and Sonoma 14.8.2 to all affected systems. 2. Enforce strict application control policies to allow installation and execution only of trusted and verified sandboxed applications, leveraging Apple’s notarization and MDM solutions. 3. Educate users on the risks of installing untrusted software and the importance of verifying app sources to reduce the likelihood of user interaction leading to exploitation. 4. Monitor endpoint behavior for unusual access patterns or attempts by sandboxed apps to access sensitive data outside their expected scope. 5. Employ data loss prevention (DLP) tools tailored for macOS environments to detect and block unauthorized data exfiltration attempts. 6. Review and tighten sandbox policies and permissions where possible to minimize data exposure. 7. Maintain up-to-date inventories of macOS devices and their patch levels to ensure compliance and rapid response to emerging threats.