CVE-2025-24135 is a vulnerability in Apple macOS that allows an application to gain elevated privileges through improper message validation. The flaw is classified under CWE-276, which relates to incorrect privilege management. Specifically, the vulnerability arises because the system fails to adequately validate messages or requests that control privilege elevation, enabling a local attacker with some privileges to escalate their access rights without requiring user interaction. The vulnerability has a CVSS v3.1 base score of 7.8, indicating high severity. The attack vector is local (AV:L), meaning the attacker must have local access to the system, and the attack complexity is low (AC:L). The attacker needs some privileges (PR:L) but does not require user interaction (UI:N). The scope is unchanged (S:U), but the impact on confidentiality, integrity, and availability is high (C:H/I:H/A:H), meaning the attacker can fully compromise the system's security. The issue was addressed by Apple in macOS Sequoia 15.3 through improved message validation mechanisms that prevent unauthorized privilege escalation. No public exploits have been reported yet, but the vulnerability presents a significant risk if exploited.

If exploited, this vulnerability allows an attacker with limited local privileges to escalate their privileges to a higher level, potentially root or system-level access. This can lead to full system compromise, including unauthorized access to sensitive data, modification or deletion of critical files, installation of persistent malware, and disruption of system availability. Organizations relying on macOS for critical operations, especially in sectors such as technology, finance, healthcare, and government, could face severe operational and reputational damage. The ability to escalate privileges locally also increases the risk posed by insider threats or attackers who have gained initial footholds through other means. Given the high impact on confidentiality, integrity, and availability, this vulnerability could facilitate advanced persistent threats and lateral movement within networks.

The primary mitigation is to update all affected macOS systems to version Sequoia 15.3 or later, where the vulnerability has been fixed. Organizations should prioritize patch deployment on devices used in sensitive or high-risk environments. Additionally, implement strict local access controls and monitor for unusual privilege escalation attempts or suspicious local activity. Employ endpoint detection and response (EDR) tools capable of detecting anomalous behavior indicative of privilege escalation. Limit the number of users with local access and enforce the principle of least privilege. Regularly audit installed applications and running processes to identify unauthorized or suspicious software. Consider using macOS security features such as System Integrity Protection (SIP) and mandatory access controls to reduce the attack surface. Finally, maintain up-to-date backups and incident response plans to quickly recover from potential compromises.