CVE-2025-43294 is a vulnerability identified in Apple macOS involving improper validation of environment variables. Environment variables are key-value pairs used by the operating system and applications to pass configuration information. In this case, the vulnerability arises because the macOS environment variable handling mechanism did not sufficiently validate input, allowing a local application with limited privileges to potentially access sensitive user data that should otherwise be protected. The flaw is categorized under CWE-284, which relates to improper access control. The vulnerability does not require user interaction to be exploited and can be triggered by a local attacker with limited privileges, meaning the attacker must have some level of access to the system but does not need elevated rights or to trick the user. The impact is limited to confidentiality, with no effect on integrity or availability of the system. Apple addressed this issue in macOS Tahoe 26 by improving validation checks on environment variables, thereby preventing unauthorized access to sensitive data. No specific affected versions were detailed, but it is implied that versions prior to Tahoe 26 are vulnerable. There are no known exploits in the wild at this time, and the CVSS score is 3.3, reflecting a low severity rating due to the limited impact and exploitation complexity.

For European organizations, the primary impact of CVE-2025-43294 is the potential unauthorized disclosure of sensitive user data on macOS devices. This could include personal information, credentials, or other confidential data accessible through environment variables. Although the vulnerability requires local access with limited privileges, it could be exploited by malicious insiders or through compromised user accounts. The confidentiality breach could lead to privacy violations, regulatory non-compliance (e.g., GDPR), and reputational damage. However, the lack of impact on system integrity or availability reduces the risk of operational disruption. Organizations heavily reliant on macOS endpoints, particularly in sectors handling sensitive data such as finance, healthcare, and government, should be vigilant. The absence of known exploits suggests a low immediate threat, but the vulnerability could be leveraged in targeted attacks or combined with other exploits to escalate privileges or move laterally within networks.

1. Upgrade all macOS devices to macOS Tahoe 26 or later, where the vulnerability is fixed. 2. Implement strict application whitelisting and limit the installation of untrusted or unnecessary applications to reduce the risk of local exploitation. 3. Enforce the principle of least privilege by restricting user and application permissions, minimizing the ability of apps to manipulate environment variables or access sensitive data. 4. Monitor local system logs and behavior for unusual access patterns or attempts to read environment variables from unauthorized processes. 5. Conduct regular security awareness training to reduce the risk of insider threats and ensure users understand the importance of safeguarding their accounts. 6. Use endpoint detection and response (EDR) solutions capable of detecting suspicious local activities related to environment variable manipulation or data access. 7. Review and harden macOS security configurations, including System Integrity Protection (SIP) and sandboxing features, to limit app capabilities.