CVE-2026-84570 in macOS
Summary
by MITRE • 09/15/2026
A logic issue was addressed with improved checks. This issue is fixed in macOS Golden Gate 27, macOS Sequoia 15.8, macOS Tahoe 26.7. An app may be able to bypass Gatekeeper checks.
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Analysis
by VulDB Data Team • 09/15/2026
The vulnerability described involves a critical logic flaw within the Apple operating system's security framework, specifically affecting components responsible for application verification and execution control. This issue was resolved in subsequent updates including macOS Golden Gate 27, macOS Sequoia 15.8, and macOS Tahoe 26.7. The core of the problem lies in a failure to properly validate certain attributes or conditions during the gatekeeping process, which is designed to ensure that only trusted software runs on user devices. By bypassing these checks, an application could execute without undergoing the necessary security scrutiny intended by Apple's Gatekeeper mechanism.
Gatekeeper serves as a primary line of defense against malicious software by verifying the developer identity and code signature integrity before allowing applications to launch. When this logic check is flawed, it creates a pathway for unsigned or improperly signed applications to run on systems that should otherwise reject them. This bypass capability undermines the fundamental assumption that all executed binaries have been vetted for known malware signatures and compliance with security policies. The flaw likely stems from an incomplete validation routine where specific edge cases or malformed inputs are not correctly flagged as unauthorized, allowing malicious actors to exploit this gap in logic rather than relying on traditional signature forgery techniques which are typically harder to achieve.
The operational impact of such a vulnerability is significant for both individual users and enterprise environments. Attackers can distribute malware disguised as legitimate applications that bypass Gatekeeper warnings or restrictions entirely. This means victims may unknowingly execute malicious code without the standard security prompts that would otherwise alert them to potential risks. In corporate settings, this could lead to unauthorized software installation, data exfiltration, or further system compromise since endpoint protection solutions often rely on these foundational OS-level checks as part of their defense-in-depth strategy. The ability to bypass Gatekeeper effectively neutralizes one of the most effective built-in defenses against drive-by downloads and social engineering attacks that target macOS users.
From a classification perspective, this issue aligns with CWE-20 Improper Input Validation or CWE-841 Improvement of Encryption Algorithms if related to signature verification logic, though it is more accurately categorized under access control failures such as CWE-269: Improper Privilege Management or CWE-755: Improper Handling of Unusual Exceptions. In the context of the MITRE ATT&CK framework, this vulnerability facilitates techniques associated with Execution via User Interaction and potentially Defense Evasion by bypassing application whitelisting mechanisms. Adversaries often seek to exploit such flaws to maintain persistence or escalate privileges without triggering alerts from security monitoring tools that depend on standard execution paths being followed correctly.
Mitigation strategies primarily involve ensuring all systems are updated to the latest stable release containing these fixes, specifically macOS Golden Gate 27, Sequoia 15.8, and Tahoe 26.7 as noted in the advisory. Administrators should enforce strict software distribution policies that prevent users from installing applications outside of approved channels whenever possible. Additionally, enabling advanced security features such as requiring administrator approval for new system-wide changes or restricting execution to identified developers can provide layered protection even if similar logic flaws are discovered in future updates. Regular auditing of installed applications and monitoring for unusual process executions can also help detect attempts to exploit this type of vulnerability before significant damage occurs.