CVE-2015-1108 in IOS
Summary
by MITRE
The Lock Screen component in Apple iOS before 8.3 does not properly enforce the limit on incorrect passcode-authentication attempts, which makes it easier for physically proximate attackers to obtain access by making many passcode guesses.
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Analysis
by VulDB Data Team • 05/03/2022
The vulnerability identified as CVE-2015-1108 resides within Apple iOS Lock Screen implementation prior to version 8.3, representing a critical security flaw that undermines the fundamental authentication mechanisms designed to protect mobile devices. This weakness specifically targets the passcode authentication system that governs access to iOS devices when they are locked, creating a significant attack surface for adversaries who can physically approach the target device. The vulnerability stems from insufficient enforcement of security policies that should limit the number of authentication attempts before implementing protective measures such as device lockout or data wiping. Attackers exploiting this flaw can systematically guess passcodes without encountering the expected rate-limiting protections that would normally prevent brute force attacks.
The technical nature of this vulnerability aligns with CWE-307, which addresses improper restriction of repeated authentication attempts, and demonstrates how inadequate implementation of authentication controls can create exploitable conditions. The flaw operates at the operating system level within iOS's security framework, specifically affecting the Lock Screen component that manages user authentication requests. The system fails to properly track and enforce the maximum number of failed passcode attempts, allowing attackers to make unlimited guesses without triggering the built-in protective measures that should activate after a predetermined threshold of unsuccessful attempts. This behavior violates fundamental security principles that require authentication systems to implement rate limiting and account lockout mechanisms to prevent automated guessing attacks.
From an operational perspective, this vulnerability creates a severe risk for iOS users whose devices are within physical proximity of potential attackers. The attack vector is particularly dangerous because it requires minimal technical skill or specialized tools, making it accessible to casual adversaries who can simply sit near a victim and attempt passcode combinations. The vulnerability is especially concerning for devices that are not locked with a complex passcode, as simple numeric combinations can be guessed relatively quickly. Attackers can leverage this weakness to access sensitive information including personal photos, messages, contacts, emails, and business data stored on the device. The impact extends beyond individual privacy concerns to potential corporate security breaches when employees use company-issued iOS devices that may contain confidential business information.
The security implications of CVE-2015-1108 align with several ATT&CK framework techniques including T1212, which covers Exploitation for Credential Access, and T1211, which involves Exploitation for Privilege Escalation. The vulnerability enables attackers to bypass authentication mechanisms through repeated guessing attempts, effectively undermining the device's security posture. Organizations and individuals using affected iOS versions face increased risk of data exposure, identity theft, and potential financial loss. The vulnerability also highlights the importance of timely security updates and patch management, as the issue was resolved in iOS 8.3 through proper implementation of authentication attempt limiting. Security professionals should note that this vulnerability demonstrates how seemingly minor implementation flaws in authentication systems can have significant security consequences, particularly when devices are accessible to unauthorized individuals in physical proximity.
Mitigation strategies for this vulnerability include immediate deployment of iOS 8.3 updates and subsequent security patches, which properly enforce passcode attempt limits. Users should also implement additional security measures such as enabling complex passcodes with alphanumeric characters rather than simple numeric combinations, configuring automatic device lock timeouts, and enabling remote wipe capabilities through mobile device management solutions. Security teams should conduct regular vulnerability assessments to identify potentially affected devices within their networks and ensure comprehensive patch management processes are in place. The vulnerability underscores the necessity of maintaining up-to-date security configurations and the importance of understanding how authentication mechanisms function at the operating system level to prevent exploitation through brute force attacks. Organizations should also consider implementing additional security controls such as device encryption and secure configuration policies to further protect against unauthorized access attempts.