CVE-2025-43195 is a vulnerability in Apple macOS stemming from improper validation of environment variables. Environment variables are used by the operating system and applications to pass configuration and runtime information. In this case, the macOS environment variable handling mechanism did not sufficiently validate input, allowing a local application to manipulate these variables to access sensitive user data improperly. The vulnerability affects multiple macOS versions before Sequoia 15.6, Sonoma 14.7.7, and Ventura 13.7.7, which include the patches that improve validation and mitigate the issue. Exploitation requires local access and user interaction but does not require elevated privileges, making it a risk primarily from malicious or compromised local applications. The vulnerability is classified under CWE-20 (Improper Input Validation), indicating that the root cause is insufficient checking of input data. The CVSS v3.1 score of 5.5 reflects a medium severity, with a vector indicating local attack vector (AV:L), low attack complexity (AC:L), no privileges required (PR:N), user interaction required (UI:R), unchanged scope (S:U), high confidentiality impact (C:H), and no impact on integrity or availability (I:N/A:N). No known exploits have been reported in the wild as of the publication date. This vulnerability could allow attackers to bypass normal data access restrictions, potentially exposing sensitive user information to unauthorized local applications.

The primary impact of CVE-2025-43195 is the unauthorized disclosure of sensitive user data on affected macOS systems. Since the vulnerability allows local applications to access data they should not, it undermines the confidentiality of user information. This can lead to privacy breaches, leakage of personal or corporate data, and potential escalation of further attacks if sensitive credentials or tokens are exposed. The requirement for local access and user interaction limits remote exploitation but does not eliminate risk in environments where users may install or run untrusted applications. Organizations relying on macOS for critical operations, especially those handling sensitive or regulated data, face increased risk of data leakage and compliance violations. The vulnerability does not affect system integrity or availability, so it is less likely to cause system crashes or data corruption. However, the confidentiality breach alone can have significant reputational and operational consequences.

1. Apply the official patches provided by Apple by upgrading to macOS Sequoia 15.6, Sonoma 14.7.7, or Ventura 13.7.7 or later versions where the vulnerability is fixed. 2. Restrict installation and execution of untrusted or unsigned applications to reduce the risk of malicious local apps exploiting this flaw. 3. Employ application whitelisting and endpoint protection solutions that monitor and control environment variable manipulation or suspicious local app behavior. 4. Educate users about the risks of running unknown applications and the importance of applying system updates promptly. 5. Implement least privilege principles to limit user permissions and reduce the impact of compromised local accounts. 6. Monitor system logs and behavior for unusual access patterns to sensitive data or environment variable changes. 7. For enterprise environments, consider deploying macOS security configurations that limit environment variable exposure and sandbox applications where possible.