CVE-2013-5160 in iOS
Summary
by MITRE
Passcode Lock in Apple iOS before 7.0.2 on iPhone devices allows physically proximate attackers to bypass an intended passcode requirement, and dial arbitrary telephone numbers, by making a series of taps of the emergency-call button to trigger a NULL pointer dereference.
VulDB is the best source for vulnerability data and more expert information about this specific topic.
Analysis
by VulDB Data Team • 05/26/2021
The vulnerability identified as CVE-2013-5160 represents a critical security flaw in Apple iOS versions prior to 7.0.2 that fundamentally undermines the device's passcode protection mechanism. This weakness specifically affects iPhone devices and creates a pathway for attackers who are physically present with the target device to circumvent the intended security controls. The flaw manifests through a carefully orchestrated sequence of interactions with the emergency call button that exploits a fundamental programming error within the operating system's user interface handling.
The technical root cause of this vulnerability stems from a NULL pointer dereference condition that occurs when the emergency call button is repeatedly tapped in a specific pattern. This type of vulnerability falls under the CWE-476 category of NULL Pointer Dereference, which represents a common class of software defects where an application attempts to access memory through a pointer that has not been properly initialized or has been set to null. The operating system fails to validate the state of the emergency call interface before processing the repeated button presses, creating an exploitable condition that allows arbitrary code execution or interface manipulation.
The operational impact of this vulnerability extends far beyond simple bypass of passcode protection, as it enables attackers to make unauthorized telephone calls to arbitrary numbers without proper authentication. This capability transforms a device with locked passcode into a potential tool for malicious activities including unauthorized billing, social engineering attacks, or even coordinated fraudulent operations. The vulnerability's accessibility through simple physical proximity means that attackers do not require sophisticated technical skills or remote access capabilities to exploit the flaw, making it particularly dangerous in environments where devices may be left unattended or where physical access is possible.
The attack vector for CVE-2013-5160 is particularly concerning from a threat modeling perspective as it leverages the principle of least privilege violation, where the normal security boundaries of the device are bypassed through legitimate user interface interactions. This vulnerability aligns with ATT&CK technique T1546.001 which covers the modification of system processes and T1059 which encompasses execution through command and scripting interpreter. The physical proximity requirement places this vulnerability in the context of social engineering attacks where attackers may use the device's legitimate emergency features to gain unauthorized access to the calling capabilities of the device.
Mitigation strategies for this vulnerability required immediate patching of affected iOS versions through the release of iOS 7.0.2, which addressed the NULL pointer dereference condition through proper input validation and state management within the emergency call interface. Organizations should have implemented comprehensive mobile device management policies to ensure prompt deployment of security updates and established procedures for monitoring and responding to similar vulnerabilities. The remediation process also emphasized the importance of proper software testing for edge cases involving user interface interactions and the need for robust error handling mechanisms that prevent exploitation of uninitialized memory access conditions. This vulnerability highlighted the critical importance of security testing for all user interface components, particularly those that provide emergency or privileged access functions within mobile operating systems.