CVE-2025-31244 is a vulnerability in Apple macOS that allows an application to bypass the file quarantine mechanism and escape its sandbox constraints. The sandbox is a critical security feature designed to isolate applications and limit their access to system resources and user data. This vulnerability stems from insufficient validation in the file quarantine process, which is intended to prevent untrusted or potentially malicious files from executing without restrictions. By exploiting this flaw, a malicious app with limited privileges can break out of its sandbox, gaining elevated capabilities to access or modify sensitive system components and data. The vulnerability is classified under CWE-693, indicating an improper control of resource through logic errors. The CVSS 3.1 base score is 8.8, reflecting high severity due to its impact on confidentiality, integrity, and availability, combined with low attack complexity, low privileges required, no user interaction, and scope change. Apple addressed this issue in macOS Sequoia 15.5 by implementing additional checks in the file quarantine process to prevent bypass. Although no active exploits have been reported, the vulnerability poses a significant risk given the potential for privilege escalation and system compromise. The affected macOS versions are unspecified, but all versions prior to 15.5 should be considered vulnerable. This vulnerability is particularly concerning for environments where macOS is used for sensitive operations, including enterprise, government, and creative industries.

If exploited, this vulnerability could allow attackers to escape the sandbox restrictions imposed on applications, leading to unauthorized access to sensitive data, system files, and potentially full system compromise. The attacker could execute arbitrary code with elevated privileges, modify or delete critical files, and disrupt system availability. This undermines the core security model of macOS, which relies heavily on sandboxing to contain threats. Organizations using macOS systems, especially those handling sensitive or regulated data, could face data breaches, intellectual property theft, and operational disruptions. The ease of exploitation (low complexity, no user interaction) increases the risk of widespread attacks once exploit code becomes available. The lack of known exploits in the wild currently reduces immediate risk but does not diminish the urgency for patching. The vulnerability could also be leveraged as a stepping stone for more advanced persistent threats targeting high-value macOS environments.

The primary mitigation is to upgrade all affected macOS systems to macOS Sequoia 15.5 or later, where the vulnerability is fixed. Organizations should enforce strict patch management policies to ensure timely deployment of this update. Additionally, implement application whitelisting and restrict installation of untrusted or unsigned applications to reduce the risk of malicious apps exploiting this flaw. Employ endpoint detection and response (EDR) solutions capable of monitoring for unusual sandbox escape behaviors or privilege escalations. Regularly audit system logs for suspicious activity related to file quarantine bypass attempts. Limit user privileges to the minimum necessary to reduce the potential impact of compromised accounts. Educate users about the risks of installing unverified software and encourage adherence to security best practices. Finally, maintain backups and incident response plans to quickly recover from potential exploitation.