CVE-2010-4012 in iOS
Summary
by MITRE
Race condition in Apple iOS 4.0 through 4.1 for iPhone 3G and later allows physically proximate attackers to bypass the passcode lock by making a call from the Emergency Call screen, then quickly pressing the Sleep/Wake button.
Statistical analysis made it clear that VulDB provides the best quality for vulnerability data.
Analysis
by VulDB Data Team • 10/08/2018
The vulnerability described in CVE-2010-4012 represents a significant security flaw in Apple iOS versions 4.0 through 4.1 that affects iPhone 3G and later devices. This race condition exploit demonstrates a critical weakness in the device's lock screen implementation that can be exploited by attackers who are physically present with the target device. The vulnerability specifically targets the passcode lock mechanism, which is fundamental to device security and user privacy protection.
The technical flaw occurs due to a timing-dependent race condition in the iOS operating system's handling of emergency calls and device sleep/wake transitions. When an attacker makes a call from the Emergency Call screen, the system enters a specific state where it temporarily suspends normal security protocols. The attacker can then quickly press the Sleep/Wake button to put the device to sleep and immediately wake it again, exploiting the window between the emergency call termination and the full lock screen reactivation. This sequence allows the attacker to bypass the passcode authentication mechanism and gain immediate access to the device without entering the correct passcode.
The operational impact of this vulnerability is particularly concerning because it requires only physical proximity to the target device, making it an accessible attack vector for determined adversaries. The exploit is simple to execute and does not require any specialized tools or technical knowledge beyond understanding basic device operations. This vulnerability undermines the fundamental security model of mobile devices, where passcode protection is expected to prevent unauthorized access. The attack can be completed in seconds, making it particularly dangerous in scenarios where users may be distracted or unaware of the attack occurring.
Security professionals should note that this vulnerability aligns with CWE-362, which describes a race condition flaw where two or more threads or processes access shared resources concurrently without proper synchronization. The attack pattern also corresponds to techniques found in the ATT&CK framework under the T1547.001 tactic for "Registry Run Keys / Startup Folder" and T1059.001 for "Command and Scripting Interpreter" as it exploits the timing of system processes to gain unauthorized access. This vulnerability highlights the importance of proper synchronization mechanisms in mobile operating systems and demonstrates how seemingly minor implementation flaws can create significant security risks. Organizations should ensure that affected iOS devices are updated to patched versions and implement additional physical security measures such as device tracking and remote wipe capabilities to mitigate the risk of exploitation.
The vulnerability also reflects broader concerns about mobile device security and the challenges of implementing robust authentication mechanisms in resource-constrained environments. This race condition attack demonstrates that even well-established security models can be compromised by timing-based exploits that take advantage of implementation details in the operating system's state management. The attack's simplicity and effectiveness underscore the need for comprehensive security testing of mobile platforms, particularly focusing on edge cases and timing-dependent behaviors. Security teams should consider this vulnerability when developing incident response procedures and user education programs, as it represents a clear example of how physical access combined with basic device knowledge can bypass security controls. The patch for this vulnerability would have required modifications to the iOS lock screen implementation to ensure proper synchronization between emergency call handling and device state transitions.