CVE-2026-84540 in macOS
Summary
by MITRE • 09/15/2026
An authorization issue was addressed with improved state management. This issue is fixed in macOS Golden Gate 27, macOS Sequoia 15.8, macOS Tahoe 26.7. An app may be able to access sensitive user data.
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Analysis
by VulDB Data Team • 09/15/2026
The vulnerability described constitutes a critical authorization flaw rooted in inadequate state management within the operating system's security architecture. In complex software environments, particularly those involving sandboxed applications and privileged services, maintaining strict separation of states is essential for enforcing least-privilege principles. When an application transitions between different operational contexts or when multiple processes interact with shared resources, improper handling of these state changes can lead to a breakdown in access control mechanisms. This specific issue indicates that the system failed to correctly validate whether an application retained appropriate permissions after certain internal state modifications occurred. Such lapses often arise from race conditions, incomplete cleanup of session tokens, or failure to re-evaluate authorization policies during context switches, allowing processes to bypass intended restrictions and retain elevated privileges beyond their initial scope.
The operational impact of this vulnerability is significant as it directly compromises the confidentiality of user data. By exploiting the flawed state management logic, a malicious or compromised application can access sensitive information that should be strictly isolated from its execution environment. This includes personal files, credentials, browsing history, and other private data protected by macOS security frameworks like Gatekeeper and sandboxing mechanisms. The ability to bypass these controls undermines the fundamental trust model of the operating system, where users rely on strict boundaries between applications to prevent unauthorized surveillance or data exfiltration. Attackers could leverage this flaw to perform stealthy data theft without triggering standard alerts associated with explicit permission requests, thereby increasing the risk of identity theft and privacy violations for end-users.
From a technical classification perspective, this vulnerability aligns closely with CWE-269, which denotes Improper Privilege Management, specifically regarding the failure to enforce proper authorization checks during state transitions. It also relates to CWE-862, Missing Authorization, as the application effectively operates without the necessary permissions for accessing specific resources due to a logic error in how access rights are maintained over time. In terms of adversary tactics, this flaw facilitates techniques associated with MITRE ATT&CK ID T1530, Data from Local System, where an attacker accesses files and directories on compromised systems that are not normally accessible. The exploitation path likely involves manipulating the application's internal state to trick the system into believing it is in a context where access is permitted, thereby bypassing standard security checks designed to protect user privacy.
Mitigation for this vulnerability requires strict adherence to secure coding practices focused on robust state management and continuous authorization validation. Developers must ensure that every operation involving sensitive resources triggers an explicit re-evaluation of the caller's privileges, regardless of previous successful accesses or current application states. Implementing defense-in-depth strategies is crucial; this includes enforcing mandatory access controls at multiple layers rather than relying solely on single-point checks. Regular security audits and static analysis should be employed to identify logic errors in permission handling. For users, applying the provided updates for macOS Golden Gate 27, Sequoia 15.8, and Tahoe 26.7 is essential as these patches contain the necessary code corrections to restore proper state validation mechanisms. Organizations should also monitor application behavior using endpoint detection and response tools that can flag unusual data access patterns indicative of privilege escalation attempts.