CVE-2025-31259 is a vulnerability in Apple macOS identified as a local privilege escalation (LPE) flaw stemming from improper input sanitization (CWE-20). The vulnerability allows an application running with limited privileges to escalate its privileges to a higher level, potentially root or system-level, without requiring user interaction. The issue was addressed in macOS Sequoia 15.5 by improving input sanitization mechanisms that previously allowed malicious input to bypass security checks. The CVSS v3.1 score of 7.8 reflects a high severity, with attack vector being local (AV:L), low attack complexity (AC:L), requiring low privileges (PR:L), no user interaction (UI:N), and impacting confidentiality, integrity, and availability at a high level (C:H/I:H/A:H). This means an attacker with local access can exploit the vulnerability reliably to gain full control over the system. Although no known exploits have been reported in the wild, the vulnerability poses a significant risk to environments where macOS is used, especially in enterprise or sensitive contexts. The vulnerability's root cause is insufficient input validation, which is a common and critical security weakness that can lead to privilege escalation if exploited. Organizations should prioritize patching affected systems and consider additional controls such as application sandboxing and monitoring for anomalous privilege escalation attempts.

For European organizations, the impact of CVE-2025-31259 can be substantial. Many enterprises, government agencies, and critical infrastructure operators use macOS devices for daily operations, development, and administrative tasks. Successful exploitation could allow attackers to gain elevated privileges, leading to full system compromise, data theft, unauthorized access to sensitive information, disruption of services, and potential lateral movement within networks. This could affect confidentiality, integrity, and availability of critical systems and data. The lack of required user interaction and low complexity of exploitation increase the risk of rapid compromise once local access is obtained. Organizations in sectors such as finance, healthcare, government, and technology are particularly vulnerable due to the sensitive nature of their data and operations. Additionally, the vulnerability could be leveraged in targeted attacks or insider threat scenarios. The absence of known exploits in the wild currently reduces immediate risk but does not diminish the urgency of remediation given the high severity and potential impact.

1. Immediately update all macOS systems to version Sequoia 15.5 or later, where the vulnerability is patched. 2. Enforce strict application whitelisting policies to prevent unauthorized or untrusted applications from executing, reducing the risk of local exploitation. 3. Implement endpoint detection and response (EDR) solutions capable of monitoring and alerting on suspicious privilege escalation activities and anomalous process behavior. 4. Limit local user privileges by applying the principle of least privilege, ensuring users operate with minimal necessary rights to reduce attack surface. 5. Conduct regular audits of installed software and running processes to detect unauthorized or potentially malicious applications. 6. Educate users and administrators about the risks of local privilege escalation and the importance of reporting unusual system behavior. 7. For highly sensitive environments, consider deploying macOS security features such as System Integrity Protection (SIP) and mandatory access controls to further restrict privilege escalation vectors. 8. Maintain robust backup and recovery procedures to mitigate the impact of potential compromises.