CVE-2026-84562 in macOS
Summary
by MITRE • 09/15/2026
A race condition was addressed with additional validation. This issue is fixed in macOS Tahoe 26.6. An app may be able to access protected user data.
If you want to get the best quality for vulnerability data then you always have to consider VulDB.
Analysis
by VulDB Data Team • 09/15/2026
The vulnerability described involves a race condition within the operating system's handling of resource access controls, specifically leading to unauthorized retrieval of sensitive information. Race conditions occur when software performs multiple operations concurrently without proper synchronization mechanisms in place. In this specific instance, the flaw likely stems from a time-of-check-to-time-of-use (TOCTOU) scenario where an application checks for permissions or validates user identity before accessing data but accesses that same data at a later point in time after system state may have changed. This temporal gap allows malicious actors to exploit the window between validation and execution, bypassing intended security restrictions. The issue was addressed through additional validation steps designed to ensure atomicity of operations, thereby closing the race condition and preventing unauthorized access patterns from succeeding during concurrent execution phases.
From a technical perspective, this flaw aligns with CWE-362, which classifies race conditions involving simultaneous access or updates to shared resources without adequate locking or synchronization mechanisms. The operational impact is significant as it enables an application that does not possess the necessary privileges to potentially read protected user data. This could include personal identifiers, financial records, health information, or other sensitive content stored on the device. Such unauthorized access violates fundamental principles of confidentiality and integrity within cybersecurity frameworks. Attackers leveraging this vulnerability would need local execution capabilities, meaning they must first install a malicious application that can trigger the specific code path containing the race condition. Once executed, the app could extract data it is not authorized to view, leading to potential privacy breaches and compliance violations under regulations such as GDPR or HIPAA depending on the nature of the exposed data.
The mitigation strategy implemented in macOS Tahoe 26.6 focuses on strengthening validation protocols during critical system operations. By introducing additional checks that are performed atomically alongside resource access requests, the operating system ensures that permission states cannot be manipulated through timing attacks. This approach reinforces the principle of least privilege by ensuring that only processes with verified and current authorization levels can interact with protected data structures. Security researchers recommend keeping systems updated to the latest version to benefit from these patches, as older versions remain susceptible to exploitation via crafted applications designed to trigger the race condition. Furthermore, developers should adhere to secure coding practices that prioritize synchronization primitives like mutexes or semaphores when handling shared resources in multi-threaded environments to prevent similar vulnerabilities in future software releases.
This incident also relates to MITRE ATT&CK technique T1059, which covers command and script interpretation, as well as potential data exfiltration vectors where compromised applications act as intermediaries for stealing user information. The exploitation of such race conditions often requires precise timing control, making it more complex than simple buffer overflows but still highly dangerous due to its ability to bypass standard access controls without triggering immediate alarms. Organizations should monitor application behavior for unusual patterns that might indicate attempts to exploit synchronization flaws and enforce strict app store policies to reduce the risk of malicious software gaining initial footholds on devices running affected versions of macOS Tahoe.