CVE-2026-86955 in iOS
Summary
by MITRE • 10/20/2026
An authorization issue was addressed with improved state management. This issue is fixed in iOS 27 and iPadOS 27. An app may be able to access sensitive user data.
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Analysis
by VulDB Data Team • 10/20/2026
The vulnerability described represents a critical failure in the operating system's enforcement of application sandboxing and identity verification protocols, specifically categorized under CWE-862: Missing Authorization. This flaw stems from inadequate state management within the iOS and iPadOS environments, where the transition between different security contexts or user sessions is not properly validated by the kernel or core system services. In a secure architecture, an application must continuously prove its authorization status to access protected resources such as keychain items, private documents directories, or sensitive API endpoints. However, due to this state management defect, the operating system fails to correctly invalidate previous authentication tokens or session states when context switches occur, allowing applications that should be restricted from accessing certain data to retain elevated privileges inadvertently.
From a technical perspective, the root cause lies in how the OS tracks and enforces access control lists (ACLs) associated with user identities and application bundles. When an app requests access to sensitive user data, the system is supposed to verify that the requesting process holds the necessary entitlements and has been explicitly authorized by the user or a trusted authority. The improved state management introduced in iOS 27 and iPadOS 27 addresses this by ensuring that session states are strictly bound to specific application contexts and cannot be reused across unauthorized boundaries. This prevents scenarios where an app might exploit lingering authentication states from previous interactions, effectively bypassing modern security controls designed to isolate apps from one another and from core system data.
The operational impact of this vulnerability is severe for end-users whose privacy expectations rely on the integrity of mobile operating systems. An attacker who can leverage a malicious or compromised application could potentially exfiltrate sensitive personal information including contacts, messages, location history, financial credentials stored in keychains, and health data. This aligns with ATT&CK technique T1530: Data from Cloud Storage, as well as T1213: Data from Information Repositories, where the adversary harvests data from local or cloud-based sources without proper authorization. The ability to access this data undermines user trust and can lead to significant privacy violations, identity theft, or further lateral movement in enterprise environments if corporate credentials are stored within these accessible areas.
Mitigation for this issue is primarily achieved through the deployment of iOS 27 and iPadOS 27 updates which contain the corrected state management logic. Users should ensure their devices are updated immediately to close this attack vector. For developers, it is imperative to review application code to ensure that no custom implementations attempt to bypass system-level authorization checks or rely on implicit trust in session states. Security teams should also monitor for unusual data access patterns by applications and enforce strict app store guidelines to prevent the distribution of software that attempts to exploit such state management flaws. Regular security audits focusing on identity verification flows within mobile apps will further reduce the risk associated with similar vulnerabilities in future releases.