CVE-2026-43789 in macOS
Summary
by MITRE • 09/15/2026
An access issue was addressed with additional sandbox restrictions. This issue is fixed in macOS Golden Gate 27, macOS Sequoia 15.8, macOS Tahoe 26.7. An app may be able to access user-sensitive data.
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Analysis
by VulDB Data Team • 09/15/2026
The vulnerability described involves a failure in the operating system's application sandboxing mechanism, specifically within Apple's macOS environment across versions including Golden Gate 27, Sequoia 15.8, and Tahoe 26.7. This issue represents a classic privilege escalation or information disclosure flaw where an untrusted application is able to bypass intended security boundaries designed to isolate it from sensitive user data. In modern operating systems like macOS, the sandbox acts as a critical defense-in-depth layer that restricts what resources an app can access by default. When this mechanism fails due to insufficient restrictions or logic errors in how permissions are evaluated, applications may gain unauthorized read access to files and directories they should not be able to reach, such as documents, photos, contacts, or other personally identifiable information stored on the user's device.
From a technical perspective, this flaw likely stems from an improper enforcement of entitlements or a race condition in the sandbox policy engine that allows an app to exploit a gap between its declared permissions and actual system access controls. The Core Foundation framework or similar low-level APIs may have been invoked by malicious code with elevated privileges due to a misconfiguration in how the kernel validates process capabilities against user-defined security policies. This type of vulnerability is often categorized under CWE-269, which refers to Improper Privilege Management, as it involves an actor obtaining access rights that exceed those intended for their level of trust. It may also align with CWE-732, concerning Incorrect Permission Assignment for Critical Resource, if the underlying file system permissions were not correctly restricted by the sandbox profile before being exposed to the application process.
The operational impact of this vulnerability is significant because it compromises user privacy and data confidentiality at a fundamental level. An attacker who can exploit this flaw does not necessarily need to compromise the operating system kernel or gain root access; instead, they only need to trick a user into installing or running a malicious app that leverages this sandbox escape vector. Once executed, the application could silently exfiltrate sensitive files in the background without triggering standard security alerts, as it is technically operating within what appears to be valid permissions from its own perspective until the data leaves the device. This undermines the trust model of macOS and poses severe risks for enterprise environments where employee or customer data must remain isolated per application boundary.
This behavior maps directly to several techniques in the MITRE ATT&CK framework, particularly T1083 File and Directory Discovery, which describes how adversaries search local systems for specific files or directories containing sensitive information. Additionally, it relates to T1564 Hidden Files and Directories if the exfiltrated data is moved to obscured locations before transmission, though the primary concern here is the initial unauthorized access itself. The exploitation of sandbox restrictions also touches upon T1059 Command and Scripting Interpreter scenarios where scripts are used to automate the gathering of system information after gaining foothold through this permission bypass.
Mitigation for this vulnerability relies primarily on applying the provided software updates that address these additional sandbox restrictions in macOS Golden Gate 27, Sequoia 15.8, and Tahoe 26.7. Administrators should ensure all endpoints are patched to enforce stricter entitlement validation and reduce the attack surface available to untrusted applications. Beyond patching, organizations should implement application whitelisting policies that prevent unsigned or unrecognized binaries from executing on critical systems. Users must also be educated about the risks of installing software from unknown sources, as this vulnerability highlights how even seemingly benign apps can become vectors for data theft if they exploit underlying OS flaws. Regular auditing of installed applications and monitoring for unusual file access patterns using endpoint detection and response tools can further help identify potential exploitation attempts in real time.