CVE-2025-43420 is a race condition vulnerability identified in Apple macOS that allows a local application to access sensitive user data improperly. The root cause is a timing issue in state handling, classified under CWE-362 (Race Condition). This flaw permits an app running with low privileges to exploit a window of inconsistent state to bypass normal access controls and read sensitive information without requiring user interaction. The vulnerability affects multiple macOS versions, specifically Sequoia 15.7.2, Sonoma 14.8.2, and Tahoe 26.1, where it has been fixed by improving state management to eliminate the race condition. The CVSS v3.1 base score is 4.7, reflecting a medium severity level, with the vector indicating local attack vector (AV:L), high attack complexity (AC:H), low privileges required (PR:L), no user interaction (UI:N), unchanged scope (S:U), high confidentiality impact (C:H), and no impact on integrity or availability (I:N/A:N). No public exploits are known, and exploitation requires precise timing and local access, limiting the attack surface primarily to environments where untrusted or malicious local apps exist. The vulnerability primarily threatens confidentiality by potentially exposing sensitive user data to unauthorized local applications.

The primary impact of CVE-2025-43420 is unauthorized disclosure of sensitive user data on affected macOS systems. Organizations relying on macOS devices, especially in environments where multiple users share systems or where untrusted applications may run, face increased risk of data leakage. This could lead to exposure of personal information, credentials, or other confidential data, undermining user privacy and organizational security. Since the vulnerability does not affect integrity or availability, it is less likely to cause system disruption or data manipulation. However, the confidentiality breach could facilitate further attacks such as identity theft, espionage, or privilege escalation if sensitive data includes authentication tokens or secrets. The requirement for local access and high attack complexity reduces the likelihood of widespread exploitation but does not eliminate risk in targeted scenarios such as insider threats or compromised endpoints. Organizations with high-value data on macOS platforms should treat this vulnerability seriously to prevent potential data breaches.

To mitigate CVE-2025-43420, organizations should promptly apply the security updates provided by Apple in macOS Sequoia 15.7.2, Sonoma 14.8.2, and Tahoe 26.1 or later versions that include the fix. Beyond patching, organizations should implement strict application control policies to limit installation and execution of untrusted or unnecessary local applications, reducing the risk of local exploitation. Employ endpoint detection and response (EDR) solutions to monitor for unusual local process behavior indicative of race condition exploitation attempts. Enforce least privilege principles to minimize the number of users and applications with local access rights. Regularly audit local user accounts and installed software to detect and remove potentially malicious or unauthorized apps. Additionally, educate users about the risks of installing unverified software and maintain robust backup and incident response plans to quickly address any data exposure incidents. Network segmentation and use of virtualization or containerization can further isolate sensitive macOS environments from untrusted local code execution.