CVE-2025-43340 is a sandbox escape vulnerability in Apple macOS identified as a permissions issue that allows an application to break out of its restricted execution environment. The sandbox mechanism in macOS is designed to isolate applications, limiting their access to system resources and user data to prevent malicious activity. This vulnerability undermines that isolation by exploiting insufficient permission restrictions, enabling an app to perform unauthorized actions outside its sandbox boundaries. The vulnerability is classified under CWE-284 (Improper Access Control), indicating that the system fails to enforce adequate access restrictions. The CVSS v3.1 base score is 7.8 (high), with vector AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H, meaning the attack requires local access and user interaction but no privileges or authentication. Exploiting this vulnerability could allow an attacker to gain elevated privileges, access sensitive information, modify system files, or disrupt system availability. The issue is fixed in macOS Tahoe 26 by implementing additional permission restrictions to strengthen sandbox enforcement. No public exploits have been reported yet, but the high impact and ease of exploitation make this a critical patch for macOS users. Organizations relying on macOS should assess their exposure and deploy the update promptly to prevent potential exploitation.

For European organizations, this vulnerability poses a significant risk, particularly for those using macOS devices in sensitive environments such as government, finance, healthcare, and critical infrastructure. A successful sandbox escape can lead to full system compromise, enabling attackers to steal confidential data, alter critical files, or disrupt operations. Given the high confidentiality, integrity, and availability impact, attackers could leverage this flaw to conduct espionage, ransomware deployment, or sabotage. The requirement for local access and user interaction limits remote exploitation but does not eliminate risk, as phishing or social engineering could facilitate initial access. Organizations with remote or hybrid workforces using macOS laptops are especially vulnerable. The absence of known exploits in the wild provides a window for proactive patching, but delayed updates increase exposure. The impact extends beyond individual devices to network security, as compromised macOS endpoints can serve as pivot points for broader attacks within corporate networks.

1. Immediately update all macOS devices to macOS Tahoe 26 or later, which contains the patch addressing this vulnerability. 2. Enforce strict application installation policies, allowing only trusted and verified apps from the Apple App Store or enterprise-approved sources. 3. Implement endpoint protection solutions capable of detecting anomalous behavior indicative of sandbox escape attempts. 4. Educate users about the risks of installing untrusted software and the importance of avoiding suspicious links or attachments that could lead to local compromise. 5. Employ least privilege principles on macOS systems, restricting user permissions to reduce the impact of potential sandbox escapes. 6. Monitor system logs and security alerts for unusual activity related to sandbox violations or privilege escalations. 7. For organizations with macOS device management, use Mobile Device Management (MDM) tools to enforce compliance and automate patch deployment. 8. Consider network segmentation to limit lateral movement from compromised macOS endpoints. 9. Regularly review and update security policies to incorporate emerging macOS-specific threat intelligence.