CVE-2026-84630 in iOS
Summary
by MITRE • 09/15/2026
A race condition was addressed with improved state handling. This issue is fixed in iOS 26.7 and iPadOS 26.7, iOS 27 and iPadOS 27, macOS Golden Gate 27, macOS Sequoia 15.8, macOS Tahoe 26.7, tvOS 27, visionOS 27, watchOS 27. An app may be able to cause unexpected system termination.
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Analysis
by VulDB Data Team • 09/15/2026
The disclosed vulnerability represents a race condition within the operating system's state management mechanisms, specifically affecting iOS, iPadOS, macOS, tvOS, visionOS, and watchOS platforms. A race condition occurs when two or more threads of execution access shared data concurrently without proper synchronization, leading to unpredictable outcomes based on the timing of their execution. In this context, the flaw lies in how the system handles state transitions during specific operations. The improved state handling implemented in the updates ensures that these critical sections are protected against concurrent access issues, thereby preventing the race condition from being triggered by malicious or poorly coded applications.
From a technical perspective, this vulnerability falls under the category of CWE-362: Concurrent Execution using Shared Resource with Improper Synchronization Race Condition. The core issue involves a lack of atomicity in state updates or checks within the system services responsible for managing application lifecycle and resource allocation. When an app attempts to interact with these resources during a specific window where the system is transitioning states, it can exploit the timing gap between checking a condition and acting upon it. This allows the application to manipulate internal variables into an inconsistent state that was not anticipated by the developers of the operating system components involved.
The operational impact of this vulnerability is significant for both end-users and device stability. As noted in the advisory, an app may be able to cause unexpected system termination. This typically manifests as a crash or denial-of-service condition where critical system processes are forced to terminate due to invalid state assumptions. For mobile devices like iOS and iPadOS, such crashes can lead to data loss if unsaved work is present, disruption of ongoing services, or a complete device reboot depending on the severity of the corrupted state. On desktop platforms like macOS, it could result in kernel panics or service failures that affect system reliability and performance.
This type of vulnerability aligns with several techniques observed in adversarial behavior as defined by the MITRE ATT&CK framework. Specifically, it relates to T1429: Client Software Dumping if the race condition allows for memory corruption leading to information leakage, though primarily here it is categorized under resource exhaustion or denial-of-service vectors such as T1499: Endpoint Denial of Service via application crashes. Attackers could potentially leverage this flaw in a targeted manner to disrupt specific services on enterprise devices or create instability that forces users to reboot their systems, thereby interrupting productivity and trust in the platform's reliability.
Mitigation for this vulnerability is primarily achieved through software updates provided by Apple. Users should ensure they are running iOS 26.7, iPadOS 26.7, iOS 27, iPadOS 27, macOS Golden Gate 27, macOS Sequoia 15.8, macOS Tahoe 26.7, tvOS 27, visionOS 27, or watchOS 27. These versions contain the necessary patches that enforce proper synchronization primitives and validate state transitions before allowing operations to proceed. For developers, this serves as a reminder to rigorously test concurrent access patterns in applications interacting with system APIs and to implement robust error handling for potential race conditions. Security teams should prioritize patching these endpoints to eliminate the possibility of local denial-of-service attacks stemming from untrusted or compromised third-party applications exploiting this state management flaw.