CVE-2025-43266 is a sandbox escape vulnerability in Apple macOS identified due to a permissions issue that allowed applications to break out of their sandbox environment. Sandboxing is a critical security mechanism in macOS designed to isolate applications and restrict their access to system resources and user data, thereby limiting the potential damage from compromised or malicious apps. This vulnerability arises from insufficient enforcement of sandbox restrictions, enabling an app to gain broader access than intended. The issue affects multiple macOS versions prior to the patched releases: macOS Sequoia 15.6, Sonoma 14.7.7, and Ventura 13.7.7. The vulnerability has a CVSS v3.1 base score of 5.1, reflecting a medium severity level. The vector string (AV:L/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:N) indicates that the attack requires local access (AV:L), low attack complexity (AC:L), no privileges (PR:N), no user interaction (UI:N), unchanged scope (S:U), and impacts confidentiality and integrity at a low level (C:L/I:L), with no impact on availability (A:N). The weakness is classified under CWE-732, which relates to incorrect permission assignment or access control. Apple has addressed this vulnerability by adding additional restrictions to the sandbox enforcement mechanism in the specified macOS versions. No public exploits or active exploitation in the wild have been reported to date. The vulnerability primarily threatens the confidentiality and integrity of data by allowing an application to access resources or data outside its sandbox, potentially leading to unauthorized data access or modification. Since the exploit requires local access, the risk is higher in environments where untrusted or less controlled applications may run locally, such as shared workstations or developer machines.

The primary impact of CVE-2025-43266 is the potential compromise of confidentiality and integrity within affected macOS systems. By escaping the sandbox, a malicious or compromised application could access files, system resources, or user data beyond its intended permissions, leading to unauthorized data disclosure or modification. This could facilitate further attacks such as privilege escalation, data theft, or persistence mechanisms. Although the vulnerability does not affect availability, the breach of sandbox boundaries undermines a fundamental security control in macOS, increasing the attack surface. Organizations relying on macOS for sensitive workloads, software development, or creative content production could face risks of data leakage or intellectual property theft. The requirement for local access limits remote exploitation, but insider threats, compromised user accounts, or malware delivered via local vectors (e.g., USB devices, phishing leading to local execution) could leverage this vulnerability. The absence of known exploits in the wild reduces immediate risk, but the medium severity score and the nature of the vulnerability warrant timely patching to prevent potential exploitation. Enterprises with macOS endpoints should consider this vulnerability in their risk assessments and endpoint security strategies.

To mitigate CVE-2025-43266, organizations should prioritize applying the security updates released by Apple in macOS Sequoia 15.6, Sonoma 14.7.7, and Ventura 13.7.7, which include enhanced sandbox restrictions addressing this vulnerability. Beyond patching, organizations should enforce strict application control policies to limit the installation and execution of untrusted or unsigned applications, reducing the risk of sandbox escape attempts. Employ endpoint detection and response (EDR) solutions capable of monitoring for anomalous behaviors indicative of sandbox breakout attempts or unauthorized access patterns. Implement least privilege principles for user accounts to minimize the impact of local exploits. Regularly audit and restrict local access to macOS systems, especially in shared or multi-user environments, to prevent unauthorized local code execution. Additionally, educate users on the risks of running untrusted software and the importance of applying system updates promptly. For high-security environments, consider deploying macOS security features such as System Integrity Protection (SIP) and mandatory access controls to further constrain application capabilities. Finally, maintain comprehensive logging and monitoring to detect any suspicious activity related to sandbox violations.