CVE-2015-8512 in Firefox OS
Summary
by MITRE
The lockscreen feature in Mozilla Firefox OS before 2.5 does not properly restrict failed authentication attempts, which makes it easier for physically proximate attackers to obtain access by entering many passcode guesses.
Be aware that VulDB is the high quality source for vulnerability data.
Analysis
by VulDB Data Team • 06/20/2018
The vulnerability identified as CVE-2015-8512 affects Mozilla Firefox OS versions prior to 2.5, specifically targeting the lockscreen authentication mechanism. This weakness represents a significant security flaw in the operating system's user authentication framework, particularly concerning the handling of failed authentication attempts. The issue stems from inadequate implementation of authentication attempt limiting mechanisms within the lockscreen functionality, creating a pathway for unauthorized access through brute force attacks. The vulnerability is classified under CWE-307, which deals with improper restriction of consecutive authentication attempts, making it a direct descendant of weak session management practices.
The technical implementation flaw lies in the absence of proper rate limiting or account lockout mechanisms within Firefox OS's lockscreen component. When users attempt to unlock their devices, the system fails to track or restrict the number of failed authentication attempts, allowing attackers to continuously guess passcodes without facing any protective measures. This design oversight enables attackers to systematically work through potential passcode combinations until they successfully gain access to the device. The vulnerability is particularly concerning because it requires only physical proximity to the device, eliminating the need for sophisticated attack vectors or network-based exploitation methods. This characteristic aligns with ATT&CK technique T1212, which involves exploitation of software vulnerabilities to gain unauthorized access through physical proximity.
The operational impact of this vulnerability extends beyond simple unauthorized access, as it fundamentally compromises the device's security posture. Physically proximate attackers can exploit this weakness to gain complete control over the device, potentially accessing sensitive personal data, installed applications, and communication channels. The ease of exploitation makes this vulnerability particularly dangerous in environments where devices may be left unattended or accessible to unauthorized individuals. Security researchers have noted that this type of vulnerability can be exploited within minutes, depending on the complexity of the passcode and the attacker's computational resources. The vulnerability affects the core security model of Firefox OS, which relies on the lockscreen as the primary barrier to unauthorized access, making it a critical weakness in the system's defense-in-depth strategy.
Mitigation strategies for CVE-2015-8512 primarily involve updating to Firefox OS version 2.5 or later, which includes proper implementation of authentication attempt limiting mechanisms. Organizations should also implement additional security measures such as strong passcode policies, enabling automatic device locking after brief periods of inactivity, and implementing remote wipe capabilities for lost or stolen devices. Security administrators should consider deploying device management solutions that can enforce additional authentication restrictions and monitor for suspicious authentication patterns. The vulnerability highlights the importance of implementing proper access control mechanisms and demonstrates how seemingly simple security features like lockscreens can become critical attack vectors when not properly implemented. Organizations should also consider conducting regular security assessments to identify similar weaknesses in authentication mechanisms across their device fleets. This vulnerability serves as a reminder of the critical importance of proper session management and authentication handling in mobile operating systems, particularly in environments where physical security controls may be insufficient.