CVE-2025-43187 is a high-severity vulnerability affecting Apple's macOS operating system, specifically related to the 'hdiutil' command-line utility. The vulnerability allows for the unexpected execution of arbitrary code when running an 'hdiutil' command. 'hdiutil' is a tool used to manipulate disk images (such as mounting, creating, and verifying them) on macOS. The root cause of this vulnerability appears to be the presence of vulnerable code within the utility that can be exploited to execute code with the privileges of the user running the command. The CVSS 3.1 base score of 7.8 indicates a high impact, with the vector string AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H showing that the attack requires local access (AV:L), low attack complexity (AC:L), low privileges (PR:L), no user interaction (UI:N), and impacts confidentiality, integrity, and availability to a high degree (C:H/I:H/A:H). The vulnerability was addressed by Apple through the removal of the vulnerable code, with fixes released in macOS Sonoma 14.7.7, Ventura 13.7.7, and Sequoia 15.6. No known exploits are currently reported in the wild. However, the potential for arbitrary code execution without user interaction and with low privileges makes this a critical issue for users of affected macOS versions. Attackers with local access could leverage this vulnerability to escalate privileges, execute malicious payloads, or compromise system integrity and availability.

For European organizations, this vulnerability poses a significant risk, especially those with macOS endpoints in their IT environment. The ability to execute arbitrary code locally without user interaction means that insider threats or attackers who have gained limited access could escalate their privileges and compromise sensitive data or disrupt operations. This could lead to data breaches, intellectual property theft, or operational downtime. Organizations in sectors such as finance, healthcare, government, and technology, which often use macOS devices, could face severe consequences including regulatory penalties under GDPR if personal data confidentiality is compromised. Additionally, the high impact on integrity and availability could disrupt critical business processes. Since the vulnerability requires local access, it may be exploited in scenarios where attackers gain physical access or through lateral movement after initial compromise, emphasizing the need for robust endpoint security and internal access controls.

European organizations should prioritize patching affected macOS systems by upgrading to macOS Sonoma 14.7.7, Ventura 13.7.7, or Sequoia 15.6 as soon as possible. Beyond patching, organizations should implement strict access controls to limit local access to macOS devices, including enforcing strong authentication mechanisms and restricting administrative privileges. Endpoint detection and response (EDR) solutions should be deployed to monitor for suspicious use of 'hdiutil' or other command-line utilities indicative of exploitation attempts. Network segmentation can reduce the risk of lateral movement if an attacker gains initial access. Regular auditing of user accounts and privilege levels will help identify and mitigate insider threats. Additionally, organizations should educate users about the risks of local exploitation and ensure physical security controls are in place to prevent unauthorized device access. Finally, maintaining up-to-date backups and incident response plans will help mitigate the impact of any successful exploitation.