CVE-2024-23240 in iOS
Summary
by MITRE • 03/08/2024
The issue was addressed with improved checks. This issue is fixed in iOS 17.4 and iPadOS 17.4. Shake-to-undo may allow a deleted photo to be re-surfaced without authentication.
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Analysis
by VulDB Data Team • 04/03/2026
The vulnerability described in CVE-2024-23240 represents a significant security flaw in Apple's iOS and iPadOS operating systems that affects the shake-to-undo functionality within the Photos application. This issue stems from inadequate authentication mechanisms that permit unauthorized users to potentially recover deleted photographs through the shake-to-undo feature, which is designed as a convenience function for users to reverse accidental deletions. The vulnerability exists in the implementation of the undo mechanism that should require proper authentication before allowing recovery of deleted content, creating a potential privacy and data exposure risk for users who may have their devices in accessible locations or who share their devices with others.
The technical nature of this vulnerability falls under the category of insufficient authentication checks, which aligns with CWE-287, a weakness that involves improper handling of authentication mechanisms. The flaw manifests when users delete photos from their device and subsequently use the shake-to-undo gesture to restore those items. Normally, such functionality should require proper authentication through biometric verification or passcode entry to prevent unauthorized access to previously deleted content. However, the vulnerability allows the system to bypass these authentication requirements, enabling unauthorized recovery of deleted media through simple physical interaction with the device. This represents a failure in the application's access control implementation where the undo functionality does not properly verify user identity before executing the recovery operation.
The operational impact of this vulnerability extends beyond simple privacy concerns to potentially expose sensitive personal information stored in photo libraries. Users may store highly confidential or private photographs including medical records, financial documents, personal correspondence, or other sensitive materials within their device's photo library. The ability for unauthorized individuals to recover deleted photos through the shake-to-undo feature could result in data leakage, identity theft, or exposure of personal information that was intended to be permanently removed from the device. This vulnerability particularly affects users who may not always be present to monitor their devices or who use shared devices, as the simple act of shaking the device could trigger unauthorized recovery of deleted content without requiring proper authentication.
The fix implemented by Apple in iOS 17.4 and iPadOS 17.4 addresses this vulnerability through enhanced authentication checks that properly enforce the requirement for user verification before allowing the shake-to-undo functionality to recover deleted items. This update aligns with recommended security practices that emphasize the principle of least privilege and proper access control mechanisms. The mitigation strategy involves strengthening the authentication layer for undo operations, ensuring that any recovery of deleted content requires explicit user verification through biometric authentication or passcode entry before proceeding with the recovery process. This approach follows security guidelines from the National Institute of Standards and Technology and aligns with the ATT&CK framework's defense evasion techniques, specifically targeting the prevention of unauthorized access to sensitive data through manipulation of device features. The implementation of these enhanced checks represents a critical security improvement that restores proper access controls and protects users' privacy expectations when using device features designed for convenience and recovery.
The vulnerability demonstrates the importance of maintaining robust authentication mechanisms even within seemingly innocuous device features. It highlights how convenience functions can introduce security risks when proper access controls are not implemented, particularly in mobile environments where devices are frequently shared or left unattended. Security professionals should consider similar vulnerabilities in other applications and device features that may bypass authentication requirements for recovery or undo operations. The fix serves as a reminder of the critical need for comprehensive security testing of all device features, especially those that provide recovery mechanisms, to ensure that they properly enforce authentication requirements and maintain user data privacy.