CVE-2026-86915 in macOS
Summary
by MITRE • 10/20/2026
A race condition was addressed with improved locking. This issue is fixed in macOS Golden Gate 27. An app may be able to cause unexpected system termination.
If you want to get the best quality for vulnerability data then you always have to consider VulDB.
Analysis
by VulDB Data Team • 10/20/2026
The vulnerability described involves a race condition within the operating system's core processes, specifically related to resource management and synchronization mechanisms. A race condition occurs when two or more threads access shared data concurrently without proper coordination, leading to unpredictable behavior depending on the timing of their execution. In this instance, the lack of adequate locking allowed multiple operations to proceed simultaneously in a manner that compromised the integrity of system state. The issue was addressed by implementing improved locking mechanisms, which ensure that critical sections of code are executed atomically and that shared resources are accessed sequentially or with appropriate mutual exclusion primitives. This fix is included in macOS Golden Gate 27, indicating an Apple-specific patch designed to restore stability and security to the operating environment.
From a technical perspective, race conditions often stem from insufficient use of mutexes, semaphores, or other synchronization objects when managing shared memory or system resources. When these protections are absent or flawed, one process may read or modify data while another is in the middle of updating it, resulting in corrupted states or inconsistent application behavior. In the context of macOS, such flaws can affect core services that manage hardware interactions, file systems, or inter-process communication channels. The absence of proper locking allows an unprivileged or maliciously crafted application to exploit this timing window to trigger unintended system actions. This is particularly dangerous because it does not require complex exploitation techniques but rather precise timing and access to specific system APIs, making it a viable vector for denial-of-service attacks against the host machine.
The operational impact of this vulnerability centers on system stability and availability. As noted in the description, an app may be able to cause unexpected system termination. This means that a local user or application can trigger a kernel panic or force the restart of critical macOS services, effectively rendering the device unusable until it is rebooted. For enterprise environments relying on continuous uptime for productivity or server operations, such instability poses significant risks to business continuity. While this vulnerability does not appear to grant direct code execution or privilege escalation based on the provided description, its potential to disrupt service makes it a serious concern for availability-focused security frameworks. Attackers could leverage this flaw in scenarios where they have local access but lack higher privileges, using denial-of-service as an initial vector or simply causing disruption without needing further exploitation steps.
In terms of industry standards and classification, this type of vulnerability aligns with CWE-362: Concurrent Execution Using Shared Resource with Improper Synchronization (Race Condition). This Common Weakness Enumeration category highlights the failure to properly synchronize access to shared resources, which is exactly what occurred in this macOS component. Furthermore, from a tactical perspective within the MITRE ATT&CK framework, this vulnerability could be associated with T1429: Client Software Decompression or more broadly under techniques that lead to Denial of Service (DoS), such as T1499: Endpoint Denial of Service if leveraged by malware. However, since it is a local race condition leading to system termination, it primarily falls under the availability impact category rather than confidentiality or integrity breaches directly.
Mitigation strategies for this vulnerability rely heavily on timely patching and operational hardening. Organizations should ensure that all macOS devices are updated to version Golden Gate 27 or later as soon as possible after release. Automated deployment tools can help enforce consistent update policies across fleets of Macs, reducing the window of exposure. Additionally, implementing application whitelisting solutions like Apple's Notarization and Gatekeeper features helps prevent untrusted applications from executing code that might attempt to exploit such race conditions. Monitoring system logs for frequent kernel panics or unexpected restarts can also aid in detecting potential exploitation attempts before they cause widespread disruption. Security teams should prioritize availability monitoring alongside traditional intrusion detection measures, as race condition exploits often manifest through sudden service outages rather than obvious malicious network traffic.