CVE-2025-43296 is a vulnerability identified in Apple macOS that stems from a logic flaw in the Gatekeeper security mechanism. Gatekeeper is designed to validate and restrict the execution of applications based on their origin and trustworthiness, preventing unauthorized or malicious apps from running without explicit user approval. The vulnerability allows an application to bypass these Gatekeeper checks, effectively circumventing this critical security control. The flaw relates to improper validation logic, which attackers could exploit to run malicious code under the guise of trusted software. According to the CVSS vector (CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:N/I:H/A:N), exploitation requires local access (AV:L), low attack complexity (AC:L), no privileges (PR:N), and user interaction (UI:R). The scope remains unchanged (S:U), with no impact on confidentiality (C:N), but a high impact on integrity (I:H) and no impact on availability (A:N). This means attackers can alter system or application integrity without leaking data or causing downtime. The vulnerability is fixed in macOS Tahoe 26, though the exact affected versions prior to this release are unspecified. No public exploits have been reported, indicating limited current active exploitation. The vulnerability is associated with CWEs 703 (Improper Check or Handling of Exceptional Conditions), 352 (Cross-Site Request Forgery), and 693 (Protection Mechanism Failure), suggesting the flaw involves improper validation and protection bypass. This vulnerability poses a risk primarily to users who might be tricked into running malicious applications, highlighting the importance of user awareness and system hardening.

For European organizations, this vulnerability could lead to unauthorized code execution on macOS endpoints, compromising system integrity. While confidentiality and availability are not directly affected, integrity breaches can enable attackers to install persistent malware, manipulate system configurations, or escalate privileges. This is particularly concerning for organizations relying on macOS for critical operations, software development, or handling sensitive data. The requirement for local access and user interaction limits remote exploitation but does not eliminate insider threats or social engineering risks. Enterprises with Bring Your Own Device (BYOD) policies or remote workforces using macOS devices may face increased exposure. The absence of known exploits reduces immediate risk but should not lead to complacency. Failure to patch could result in targeted attacks against high-value assets, intellectual property theft, or sabotage. Regulatory compliance frameworks in Europe, such as GDPR, may consider integrity compromises as reportable incidents if they affect personal data processing.

European organizations should prioritize upgrading to macOS Tahoe 26 or later to apply the official fix. Until patching is complete, implement application whitelisting to restrict execution to verified software. Enhance endpoint detection and response (EDR) capabilities to identify anomalous app behaviors indicative of Gatekeeper bypass attempts. Conduct user training focused on recognizing and avoiding suspicious application installations and social engineering tactics. Employ strict device management policies, including restricting local administrative privileges and enforcing secure configuration baselines. Regularly audit macOS systems for unauthorized software and review Gatekeeper logs where available. Consider network segmentation to limit the impact of compromised endpoints. Collaborate with Apple support channels for guidance on interim mitigations and monitor threat intelligence feeds for emerging exploit reports. Finally, integrate this vulnerability into incident response plans to ensure rapid containment if exploitation is detected.