CVE-2017-2375 in iOS
Summary
by MITRE • 12/23/2021
An issue existed in preventing the uploading of CallKit call history to iCloud. This issue was addressed through improved logic. This issue is fixed in iOS 10.2.1. Updates for CallKit call history are sent to iCloud.
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Analysis
by VulDB Data Team • 12/27/2021
The vulnerability described in CVE-2017-2375 represents a security flaw within Apple's iOS operating system that affected the CallKit framework's handling of call history data synchronization with iCloud services. This issue specifically pertained to the mechanism responsible for determining when and how call history information should be uploaded to Apple's cloud infrastructure. The problem manifested as an inadequate prevention system that failed to properly manage the upload process, potentially leaving sensitive communication data in an inconsistent state between local device storage and remote iCloud synchronization. The vulnerability existed in iOS versions prior to 10.2.1, where the logic governing iCloud synchronization for CallKit call history was insufficiently robust.
The technical nature of this flaw can be categorized under CWE-200, which deals with exposure of sensitive information to an unauthorized actor, and more specifically relates to improper access control mechanisms within the mobile operating system's data synchronization framework. The vulnerability stemmed from the absence of proper validation and authorization checks during the call history upload process, allowing for potential data inconsistencies and unauthorized data exposure. This issue was particularly concerning within the context of mobile communication security, as call history data contains sensitive personal information including contact relationships, communication patterns, and potentially confidential business or personal interactions. The flaw essentially created a gap in the system's ability to ensure that call history data was properly synchronized and securely managed across different device states and network conditions.
The operational impact of this vulnerability extended beyond simple data synchronization issues to encompass broader privacy and security concerns for iOS users. When call history data was not properly uploaded to iCloud, users faced potential data loss during device failures, migrations, or when switching between different iOS devices. The inconsistent state of call history synchronization could have created confusion in call log management and potentially exposed users to privacy risks if partial data was accessible through alternative means. This vulnerability particularly affected users who relied heavily on iCloud synchronization for maintaining consistent communication records across their Apple ecosystem. The issue also represented a failure in the system's integrity checking mechanisms, as the lack of proper upload validation could have allowed for silent data corruption or loss scenarios that went undetected by both users and system administrators.
Apple's resolution of this vulnerability through iOS 10.2.1 involved implementing enhanced logic and validation mechanisms within the CallKit framework to ensure proper handling of call history data during iCloud synchronization processes. The update addressed the root cause by strengthening the access control and authorization checks that govern when and how call history information is transmitted to iCloud services. This fix aligned with industry best practices for mobile platform security and data integrity management, ensuring that sensitive communication data was properly protected during synchronization operations. The remediation approach demonstrated Apple's commitment to maintaining secure data handling practices within their mobile operating system, particularly for frameworks that deal with sensitive user communication data. Security professionals should note that this vulnerability highlighted the importance of proper data synchronization logic in mobile operating systems and the potential privacy implications of inadequate access controls in communication frameworks. The fix represented a standard security improvement that aligned with the principles of secure software development and proper handling of sensitive data within enterprise and consumer mobile environments.