CVE-2017-13891 in iOS
Summary
by MITRE
In iOS before 11.2, an inconsistent user interface issue was addressed through improved state management.
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Analysis
by VulDB Data Team • 04/28/2020
The vulnerability identified as CVE-2017-13891 represents a user interface inconsistency issue present in iOS versions prior to 11.2. This flaw falls under the broader category of user interface security concerns that can potentially be exploited to manipulate user interactions or create confusion during system operations. The issue stems from inadequate state management within the iOS framework, which governs how the operating system maintains and transitions between different user interface states during various operations.
The technical root cause of this vulnerability lies in the improper handling of user interface states, where the system fails to maintain consistent visual representations of application interfaces across different operational contexts. This inconsistency can manifest when users interact with applications or system components, leading to scenarios where the interface does not accurately reflect the underlying system state. Such state management failures can create opportunities for attackers to exploit the inconsistent behavior to manipulate user interactions or potentially gain unauthorized access to system resources.
From an operational perspective, this vulnerability poses significant risks to user security and system integrity. The inconsistent user interface behavior could be leveraged to create deceptive user experiences that might trick users into performing unintended actions, potentially leading to unauthorized data access or system manipulation. Users might encounter situations where interface elements appear to indicate one state while the system is actually operating in another, creating confusion that could be exploited by malicious actors. The vulnerability particularly affects scenarios involving multi-step operations, system transitions, or applications that require precise user interface feedback for proper operation.
The remediation for CVE-2017-13891 required Apple to implement improved state management mechanisms within iOS 11.2 and subsequent versions. This enhancement addresses the underlying inconsistency by ensuring that user interface elements accurately reflect system states throughout all operational contexts. The fix demonstrates the importance of maintaining consistent user interface behavior as a security control mechanism, aligning with security best practices that emphasize the need for predictable and reliable system behavior. This vulnerability also relates to CWE-691, which addresses insufficient control of a resource through a public interface, and can be mapped to ATT&CK technique T1059 where attackers might exploit inconsistent interface states to manipulate user behavior or system operations. The resolution underscores the critical nature of proper state management in preventing user interface-based security exploits and highlights the necessity of comprehensive testing across all user interface scenarios to identify and address potential inconsistencies that could be leveraged by adversaries.