CVE-2025-31187 is a vulnerability identified in Apple macOS that permits an application to modify protected parts of the file system, violating intended access controls. The root cause is an access control weakness (CWE-284) where the system fails to properly restrict modification rights to critical file system areas. This flaw allows an unprivileged app, with user interaction, to alter system files or directories that should be protected, potentially undermining system integrity. The vulnerability does not grant direct confidentiality breaches or availability disruptions but can enable attackers to implant persistent malicious code or tamper with system components, complicating detection and remediation. The CVSS v3.1 score of 5.5 (medium severity) reflects the local attack vector requiring user interaction but no privileges. Apple addressed this issue by removing the vulnerable code in macOS Sequoia 15.4, Sonoma 14.7.5, and Ventura 13.7.5. No public exploits have been reported, indicating limited current exploitation but a clear risk if weaponized. The vulnerability underscores the importance of strict access control enforcement in operating system design to prevent unauthorized system modifications by apps.

The primary impact of CVE-2025-31187 is on system integrity, as it allows unauthorized modification of protected file system areas by an app. This can lead to persistent malware installation, tampering with security-critical files, or undermining system stability. Organizations relying on macOS for critical operations, software development, or sensitive data processing may face increased risk of targeted attacks aiming to implant backdoors or disrupt system trustworthiness. Although confidentiality and availability are not directly affected, integrity compromises can facilitate further attacks that may escalate privileges or exfiltrate data. The requirement for local access and user interaction limits remote exploitation but does not eliminate risk, especially in environments where users may be tricked into running malicious apps. The absence of known exploits currently reduces immediate risk but does not preclude future exploitation attempts. Overall, the vulnerability poses a moderate threat to organizations with macOS deployments, particularly those in sectors like technology, finance, and government.

To mitigate CVE-2025-31187, organizations should immediately apply the security updates provided by Apple in macOS Sequoia 15.4, Sonoma 14.7.5, and Ventura 13.7.5 or later. Beyond patching, implement strict application control policies to restrict installation and execution of untrusted or unsigned applications, reducing the risk of malicious apps exploiting this vulnerability. Employ endpoint protection solutions capable of detecting unauthorized file system modifications and monitor system integrity regularly using tools like Apple’s System Integrity Protection (SIP) and third-party integrity checkers. Educate users about the risks of installing unverified software and the importance of cautious interaction with app prompts. Limit local user privileges where possible to reduce the attack surface. Additionally, conduct regular audits of file system permissions and monitor logs for suspicious activity indicative of exploitation attempts. These layered defenses will help prevent exploitation even if patching is delayed.