CVE-2024-23238 is a vulnerability in Apple macOS that stems from inadequate access control allowing an application to edit NVRAM (Non-Volatile Random-Access Memory) variables. NVRAM stores critical system settings such as boot arguments, device configurations, and security parameters that persist across reboots. Unauthorized modification of these variables can compromise system integrity and confidentiality by altering boot behavior, bypassing security controls, or persisting malicious configurations. The vulnerability requires local access with no privileges (PR:N) and user interaction (UI:R), indicating that an attacker must convince a user to run a malicious app locally. The attack complexity is low (AC:L), making exploitation feasible if local access is gained. The CVSS v3.1 score is 7.1 (high), reflecting the significant impact on confidentiality and integrity, though availability is unaffected. Apple addressed this issue by improving access restrictions in macOS Sonoma 14.4, preventing unauthorized apps from modifying NVRAM variables. No public exploits are known at this time, but the vulnerability is critical due to the sensitive nature of NVRAM data and the potential for persistent system compromise.

For European organizations, this vulnerability poses a significant risk especially in environments where macOS devices are used for sensitive operations or hold critical data. Unauthorized modification of NVRAM variables can lead to persistent malware infections, bypass of security mechanisms such as Secure Boot, or unauthorized changes to system configurations that undermine system integrity. This can result in data breaches, loss of trust in system security, and operational disruptions. Sectors such as finance, government, healthcare, and critical infrastructure that rely on Apple hardware could face targeted attacks exploiting this vulnerability. The requirement for local access and user interaction somewhat limits remote exploitation but insider threats or social engineering attacks could leverage this flaw. The absence of known exploits reduces immediate risk but the high severity score and potential impact necessitate proactive mitigation.

1. Immediately update all macOS devices to version Sonoma 14.4 or later, where the vulnerability is patched. 2. Enforce strict local user access controls and limit installation of untrusted applications to reduce the risk of malicious app execution. 3. Employ endpoint protection solutions capable of detecting suspicious local activities and unauthorized attempts to modify system settings. 4. Educate users about the risks of running unverified applications and the importance of cautious user interaction to prevent social engineering exploitation. 5. Regularly audit NVRAM variables and system configurations for unauthorized changes using automated tools or scripts. 6. Implement device management policies that restrict local administrative privileges and application installation rights. 7. Monitor security advisories for any emerging exploits and apply additional mitigations as necessary.