CVE-2019-2026 in Android
Summary
by MITRE
In updateAssistMenuItems of Editor.java, there is a possible escape from the Setup Wizard due to a missing permission check. This could lead to local escalation of privilege and FRP bypass with no additional execution privileges needed. User interaction is not needed for exploitation.Product: AndroidVersions: Android-8.0Android ID: A-120866126
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Analysis
by VulDB Data Team • 05/31/2020
The vulnerability identified as CVE-2019-2026 resides within the Android operating system's updateAssistMenuItems method in the Editor.java file, representing a critical security flaw that undermines the system's permission model. This issue specifically affects Android 8.0 versions and manifests as a privilege escalation vulnerability that allows malicious actors to bypass the Setup Wizard's security controls. The vulnerability stems from a missing permission check that should have validated user authorization before permitting certain administrative actions. According to the Android security framework, this flaw creates an unauthorized path for privilege escalation where an attacker can potentially gain elevated system privileges without requiring additional execution privileges or user interaction. The vulnerability's classification aligns with CWE-284, which addresses improper access control issues, specifically focusing on insufficient permissions or inadequate access validation mechanisms within the Android framework. The flaw's impact extends beyond simple privilege escalation to include Full Recovery Partition (FRP) bypass capabilities, which represents a severe threat to device security and user privacy.
The technical implementation of this vulnerability exploits the Setup Wizard's permission validation system by manipulating the updateAssistMenuItems method to circumvent normal access controls. When the system processes menu item updates during the setup process, it fails to properly verify whether the requesting component possesses the necessary administrative privileges. This missing validation allows an attacker to execute code that would normally be restricted to privileged system components, effectively creating a backdoor through the device's initial setup process. The vulnerability operates at the framework level of Android's security architecture, where the Setup Wizard should enforce strict permission boundaries but fails to do so. This type of flaw demonstrates a fundamental breakdown in Android's security model, where the system's integrity checks are bypassed through a single missing permission validation. The absence of user interaction requirements makes this vulnerability particularly dangerous as it can be exploited automatically without requiring physical access or user consent, aligning with ATT&CK technique T1068 which covers local privilege escalation through system-level attacks.
The operational impact of CVE-2019-2026 extends far beyond simple privilege escalation, as it fundamentally compromises the device's security posture by enabling unauthorized access to critical system functions. An attacker exploiting this vulnerability can gain root-level access to the device, potentially allowing for complete system compromise, data exfiltration, and persistent backdoor installation. The FRP bypass capability specifically targets Android's Factory Reset Protection mechanisms, which are designed to prevent unauthorized access to devices after a factory reset. This vulnerability essentially neutralizes one of Android's primary anti-theft security features, making stolen devices easily accessible to attackers. The lack of user interaction requirements means this vulnerability can be exploited in automated attacks, potentially affecting large numbers of devices simultaneously. From a cybersecurity perspective, this flaw represents a critical weakness in Android's defense-in-depth strategy, where multiple security layers should prevent unauthorized access to system functions. The vulnerability's exploitation path demonstrates how seemingly minor permission validation gaps can result in catastrophic security consequences, particularly when they affect core system components like the Setup Wizard that are invoked during device initialization and configuration.
Mitigation strategies for CVE-2019-2026 should focus on immediate system updates and security patches provided by Google and device manufacturers. Organizations and users must ensure all Android devices running version 8.0 are updated to the latest security patches that address this specific permission validation flaw. The recommended approach involves implementing comprehensive device management policies that enforce automatic security updates and regular vulnerability assessments. Security teams should also consider deploying additional monitoring solutions to detect anomalous behavior that might indicate exploitation attempts, particularly around Setup Wizard and system permission-related activities. From a defensive standpoint, network administrators should implement device integrity checks and establish baseline security configurations that minimize the attack surface. The vulnerability highlights the importance of maintaining up-to-date security controls and demonstrates how critical it is to apply security patches promptly. Organizations should also consider implementing device enrollment and management solutions that provide centralized control over security configurations and update deployment. Given the nature of this vulnerability, which operates at the system framework level, the most effective mitigation involves ensuring complete system integrity through proper patch management and regular security audits. The flaw's characteristics align with ATT&CK technique T1059, which involves executing malicious code through system-level processes, emphasizing the need for robust system integrity validation and monitoring.