CVE-2025-24121 is a logic flaw vulnerability identified in Apple macOS operating systems that permits an application with limited privileges to modify protected parts of the file system. The root cause is insufficient validation or enforcement of access control logic, categorized under CWE-863 (Incorrect Authorization). This flaw allows a local app to bypass intended restrictions and alter system files or directories that should be protected, potentially compromising system integrity. The vulnerability does not impact confidentiality or availability directly, nor does it require user interaction, but it does require local privileges (PR:L) and has low attack complexity (AC:L). The issue was addressed by Apple through improved checks in macOS Sequoia 15.3, Sonoma 14.7.3, and Ventura 13.7.3 updates. No public exploits have been reported, indicating limited active exploitation. The vulnerability's CVSS v3.1 score is 3.3, reflecting its low severity. However, the ability to modify protected file system areas could be leveraged in chained attacks or privilege escalation scenarios. The vulnerability affects all prior versions before the patches and is relevant to environments where macOS is widely deployed.

The primary impact of CVE-2025-24121 is on system integrity, as unauthorized modification of protected file system areas can undermine trust in the operating system and potentially allow persistence mechanisms or tampering with security controls. While confidentiality and availability are not directly affected, the integrity compromise can facilitate further attacks such as privilege escalation or malware persistence. For organizations, this could lead to unauthorized changes to critical system files, weakening endpoint security and increasing the risk of advanced persistent threats. The requirement for local privileges limits remote exploitation, but insider threats or malware already running with user-level access could exploit this vulnerability. The lack of user interaction requirement makes exploitation easier once local access is obtained. Overall, the impact is moderate in controlled environments but could be significant in high-security or sensitive contexts.

To mitigate CVE-2025-24121, organizations should prioritize updating affected macOS systems to versions Sequoia 15.3, Sonoma 14.7.3, or Ventura 13.7.3 or later, where the vulnerability is patched. Additionally, implement strict application control policies to limit installation and execution of untrusted or unsigned applications, reducing the risk of local exploitation. Employ endpoint detection and response (EDR) solutions to monitor for suspicious file system modifications, especially in protected directories. Enforce the principle of least privilege by restricting user accounts and avoiding unnecessary local admin rights. Regularly audit system integrity using tools like Apple’s System Integrity Protection (SIP) and verify that it is enabled and functioning correctly. For environments with sensitive data, consider additional hardening such as disk encryption and monitoring for anomalous behavior indicative of exploitation attempts. Finally, educate users about the risks of running untrusted software locally.