CVE-2019-20570 in Samsung
Summary
by MITRE
An issue was discovered on Samsung mobile devices with P(9.0), O(8.0), and N(7.1) software. Attackers can bypass Factory Reset Protection (FRP) via Smart Switch. The Samsung ID is SVE-2019-15138 (September 2019).
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Analysis
by VulDB Data Team • 10/04/2020
This vulnerability represents a critical security flaw in Samsung mobile devices running Android Pie 9.0, Oreo 8.0, and Nougat 7.1 operating systems. The issue specifically affects the Factory Reset Protection mechanism, which is designed to prevent unauthorized use of devices after a factory reset. The vulnerability allows attackers to bypass this essential security feature through the Smart Switch application, a legitimate Samsung tool used for transferring data between devices. This bypass capability fundamentally undermines the device's security posture and creates significant risks for device owners.
The technical flaw stems from improper validation within the Smart Switch application's implementation of the FRP bypass process. When users attempt to perform a factory reset on a Samsung device, the system should require authentication using the associated Samsung account credentials. However, the vulnerability enables attackers to manipulate the data transfer process to circumvent these authentication requirements. This flaw operates at the application layer and leverages weaknesses in how the Smart Switch handles device state transitions during factory reset operations. The vulnerability is categorized under CWE-284, which addresses improper access control, and specifically relates to weak controls in device security mechanisms. The attack vector is particularly concerning as it does not require physical access to the device but can be exploited through the Smart Switch data transfer functionality.
The operational impact of this vulnerability extends beyond individual device security to affect broader ecosystem trust and user confidence. An attacker who successfully exploits this vulnerability can effectively unlock any Samsung device that has been factory reset, regardless of whether the device was previously enrolled in a Samsung account or protected by FRP. This creates opportunities for device theft, unauthorized data access, and potential exploitation of sensitive information stored on the device. The vulnerability also enables attackers to bypass the security model that Samsung implemented to protect users from device recovery after theft. According to ATT&CK framework, this vulnerability maps to T1552.001 (Credentials in Files) and T1078 (Valid Accounts) as attackers can leverage stolen credentials or bypass authentication mechanisms to gain unauthorized access. The risk is particularly elevated in enterprise environments where stolen devices could provide access to corporate networks and sensitive data.
Samsung addressed this vulnerability through software updates that strengthened the validation mechanisms within Smart Switch and improved the authentication requirements for FRP bypass operations. The fix involved implementing additional checks to ensure that proper authentication occurs before allowing device state transitions, particularly during data transfer operations. Security professionals should ensure that all Samsung devices running affected Android versions receive the latest security patches immediately. Organizations should also implement device management policies that enforce automatic security updates and monitor for unauthorized device access attempts. The vulnerability highlights the importance of validating all data transfer processes and maintaining robust authentication controls even in legitimate administrative tools. Regular security assessments of device management applications and their integration points with core security features are essential to prevent similar vulnerabilities from emerging in the future.