Description

A race condition was addressed with additional validation. This issue is fixed in iOS 27 and iPadOS 27, macOS Golden Gate 27, tvOS 27, visionOS 27, watchOS 27. A local user may be able to cause unexpected system termination or read kernel memory.

Executive Summary

Technical Details

Mitigations

References

Additional Metadata

{
  "score": "8.1",
  "pubDate": "2026-09-14T21:17:25.163Z",
  "pubdate": "2026-09-14T21:17:25.163Z",
  "executiveSummary": "A critical race condition vulnerability has been identified within the kernel of several Apple operating systems, including iOS 27, iPadOS 27, macOS Golden Gate 27, tvOS 27, visionOS 27, and watchOS 27.\nThe vulnerability stems from improper synchronization or validation, potentially allowing a local, authenticated user to trigger an unexpected system termination (Kernel Panic) or perform unauthorized reads of sensitive kernel memory.\nThis represents a significant security risk, as memory disclosure can expose kernel pointers or data structures, facilitating the bypassing of address space layout randomization (ASLR) and other defensive mitigations.\nSuccessful exploitation requires the attacker to have local access to the system, though no specific administrative privileges are explicitly stated as a prerequisite, suggesting the potential for escalation from a low-privileged context.\nThe primary impact is a loss of system availability through crash induction and a breach of system confidentiality through unauthorized kernel memory access.",
  "technicalDetails": "The root cause of this vulnerability is a race condition within the kernel's resource management or synchronization logic. In multi-threaded environments, race conditions occur when the timing or sequence of events impacts the correctness of shared state. If the kernel fails to ensure atomic access to sensitive structures—such as memory buffers, task descriptors, or object references—an attacker can exploit this window of inconsistency.\nThe exploitation flow typically begins with an attacker manipulating the execution timing of specific system calls or kernel operations that interact with a shared, vulnerable resource. By creating a high-contention scenario, an attacker can cause the kernel to access an object that is in a transitionary or invalid state.\nIf the race condition involves a Use-After-Free (UAF) or a Time-of-Check to Time-of-Use (TOCTOU) condition, the kernel might perform operations on an object that has been deallocated or modified. This can lead to the kernel reading data from unintended memory locations, effectively dumping kernel memory contents into a user-accessible buffer.\nConversely, by forcing the kernel into an inconsistent state, an attacker may trigger an assertion failure or an invalid memory access, leading to a system-wide kernel panic and immediate system termination. This is often leveraged to disrupt services or as a component in a multi-stage exploit chain.\nThe vulnerability affects multiple platforms (iOS 27, iPadOS 27, macOS Golden Gate 27, tvOS 27, visionOS 27, watchOS 27), indicating the shared architectural kernel components across these operating systems are the point of failure. The lack of proper validation at the point of interaction between user-mode requests and kernel-mode data structures allows the race to be winnable by an unprivileged user process. Attackers would require local execution capability to submit the malicious race-inducing payloads, usually through specific system calls (syscalls) that invoke the vulnerable subsystem.\nPost-exploitation impact includes the ability to bypass kernel-level protection mechanisms. By reading kernel memory, an attacker could potentially derive the base address of the kernel or identify the location of specific security structures, which is a prerequisite for more sophisticated kernel-mode arbitrary code execution exploits. The integrity of the system is effectively compromised as the boundary between user-space and kernel-space security is violated."
}