CVE-2025-43291 is a medium-severity vulnerability affecting Apple macOS operating systems, specifically versions prior to macOS Sequoia 15.7, macOS Sonoma 14.8, and macOS Tahoe 26 where the issue has been fixed. The vulnerability stems from a permissions issue (CWE-284) that allowed an application to modify protected parts of the file system. This implies that an unprivileged app, possibly without requiring prior authentication (PR:N), but requiring user interaction (UI:R), could escalate its privileges to alter critical system files or directories that are normally safeguarded by the operating system. The CVSS vector (CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:N/I:H/A:N) indicates that the attack requires local access (AV:L), low attack complexity (AC:L), no privileges required (PR:N), but user interaction is necessary (UI:R). The impact is limited to integrity (I:H) with no confidentiality or availability impact. The vulnerability was addressed by removing the vulnerable code in the specified macOS versions, eliminating the permissions flaw. There are no known exploits in the wild at the time of publication, and no patch links were provided, but users are advised to update to the fixed versions. This vulnerability is significant because it allows modification of protected filesystem areas, potentially enabling persistence mechanisms, tampering with system binaries, or bypassing security controls, which could facilitate further attacks or malware installation.

For European organizations, this vulnerability poses a moderate risk primarily to environments where macOS devices are used extensively, such as in creative industries, software development, and certain corporate sectors. The ability for an app to modify protected filesystem parts could lead to unauthorized changes in system behavior, installation of persistent malware, or circumvention of security policies. While the attack requires local access and user interaction, insider threats or social engineering attacks could exploit this vulnerability. The integrity compromise could affect system reliability and trustworthiness, potentially disrupting business operations or leading to data manipulation. Given the widespread use of macOS in some European countries, organizations with mixed OS environments need to be vigilant. However, the lack of confidentiality or availability impact and the requirement for user interaction somewhat limit the scope of damage. Still, targeted attacks against high-value macOS endpoints in sectors like finance, media, or government could leverage this flaw for privilege escalation or lateral movement.

European organizations should prioritize updating all macOS devices to the patched versions: macOS Sequoia 15.7, macOS Sonoma 14.8, or macOS Tahoe 26 as soon as possible. Beyond patching, organizations should implement strict application control policies to limit installation and execution of untrusted or unsigned applications, reducing the risk of malicious apps exploiting this vulnerability. Employ endpoint detection and response (EDR) solutions capable of monitoring filesystem changes in protected areas to detect suspicious activity. User education is critical to minimize risky behaviors that could lead to user interaction exploitation, such as opening untrusted apps or files. Additionally, enforcing least privilege principles and restricting local user permissions can reduce the attack surface. Regular audits of system integrity and file system permissions can help identify unauthorized modifications early. For environments where patching is delayed, consider deploying temporary mitigations such as disabling or restricting the use of vulnerable macOS versions or isolating affected devices from sensitive networks.