CVE-2026-84623 in iOS
Summary
by MITRE • 09/15/2026
An authorization issue was addressed with improved state management. This issue is fixed in iOS 26.7 and iPadOS 26.7, iOS 27 and iPadOS 27. An app may be able to fingerprint the device.
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Analysis
by VulDB Data Team • 09/15/2026
The vulnerability described involves a flaw in the authorization mechanisms within Apple's operating systems, specifically affecting iOS and iPadOS versions prior to 26.7 and 27. This issue stems from inadequate state management during authentication or session handling processes. When an application interacts with system services that require elevated privileges or specific user context, improper maintenance of these states can lead to a breakdown in the expected security boundaries. In this particular case, the failure allows applications to gather detailed information about the device environment that should otherwise remain isolated from third-party software. This capability enables what is known as device fingerprinting, where an app constructs a unique profile based on hardware identifiers, configuration settings, and other persistent system attributes.
From a technical perspective, this flaw represents a classic example of broken access control combined with information leakage. The application leverages the mismanaged state to bypass restrictions that are designed to limit data exposure. By accessing sensitive device characteristics without proper authorization checks or by exploiting race conditions in session handling, the app can compile a comprehensive set of identifiers. These may include unique hardware serial numbers, MAC addresses, battery health metrics, storage capacity details, and even subtle variations in sensor calibration data. This aggregated information creates a highly distinctive signature that can be used to track users across different sessions or applications without their explicit consent.
The operational impact of this vulnerability is significant for user privacy and security. Device fingerprinting undermines the principle of least privilege by allowing apps to collect more data than necessary for their core functionality. For end-users, this means reduced anonymity on their devices, as advertisers, trackers, or malicious actors can use these fingerprints to build persistent profiles. This profiling capability facilitates targeted advertising but also increases the risk of surveillance and potential exploitation if combined with other vulnerabilities. Furthermore, it erodes trust in the operating system's ability to protect user data from unauthorized collection by installed applications.
This issue aligns closely with CWE-284 Improper Access Control, as the application was able to access resources or information beyond its intended permissions due to flawed state management logic. It also relates to CWE-200 Information Exposure, where sensitive system details are revealed to an unauthorized entity. In terms of offensive security frameworks like MITRE ATT&CK, this behavior corresponds to techniques such as T1592 Gather Victim Host Information and T1614 System Location Discovery. These categories highlight how attackers or malicious apps can enumerate device-specific attributes to establish a baseline for further exploitation or long-term tracking campaigns.
Mitigation strategies primarily involve the software updates provided by Apple in iOS 26.7, iPadOS 26.7, iOS 27, and iPadOS 27. These releases address the root cause by enforcing stricter state management protocols during authorization checks. Developers should ensure that their applications adhere to modern privacy guidelines and avoid requesting unnecessary device identifiers. For system administrators and users, keeping devices updated is critical to closing these gaps in access control. Additionally, implementing runtime application self-protection mechanisms or using mobile threat defense solutions can help detect anomalous behavior indicative of fingerprinting attempts, providing an additional layer of security against such information leakage vulnerabilities.