CVE-2019-20550 in Samsung
Summary
by MITRE
An issue was discovered on Samsung mobile devices with O(8.x) (released in China and India) software. The S Secure app can access the content of a locked app without a password. The Samsung ID is SVE-2019-13805 (October 2019).
If you want to get best quality of vulnerability data, you may have to visit VulDB.
Analysis
by VulDB Data Team • 10/04/2020
The vulnerability identified as CVE-2019-20550 represents a critical security flaw in Samsung mobile devices running Android 8.x operating system versions, specifically those released in China and India markets. This issue resides within the S Secure application which is designed to provide enhanced security features for Samsung devices. The vulnerability stems from improper access controls within the secure application framework that allows unauthorized access to protected application content. The flaw essentially undermines the fundamental security principle of authentication and authorization by enabling malicious actors or unauthorized applications to bypass the standard password protection mechanisms that should govern access to locked applications.
The technical implementation of this vulnerability involves a privilege escalation flaw within the Samsung S Secure application's access control system. When users lock their applications, the system should enforce strict authentication requirements before granting access to sensitive content. However, the vulnerability allows the S Secure application to circumvent these authentication checks through a flaw in its permission model or security token handling. This weakness creates an access path that bypasses the standard lock screen authentication mechanisms, effectively allowing the secure app to read and potentially manipulate content from locked applications without requiring the user's password or biometric authentication. The vulnerability manifests as a failure in the security boundary enforcement that should separate protected application data from unauthorized access attempts.
The operational impact of this vulnerability extends beyond simple data exposure, creating a comprehensive security risk for Samsung device users in the affected markets. Attackers could exploit this flaw to gain access to sensitive personal information, financial data, messages, and other confidential content stored within locked applications. The vulnerability particularly affects users who rely on the lock screen protection for privacy and security, as it essentially renders these protections ineffective. From an attacker perspective, this represents a significant escalation opportunity that could lead to identity theft, financial fraud, or other malicious activities. The vulnerability also impacts the overall security posture of Samsung devices, potentially undermining user trust in the platform's security capabilities and creating a vector for more sophisticated attacks that could leverage this weakness as a foothold for additional exploitation.
Security professionals should note that this vulnerability aligns with CWE-284, which addresses improper access control issues in software systems. The flaw demonstrates a clear breakdown in the principle of least privilege, where the S Secure application operates with elevated permissions that should be restricted. Additionally, from an ATT&CK framework perspective, this vulnerability maps to techniques involving privilege escalation and credential access, specifically T1078 for valid accounts and T1548 for abuse of privileges. Organizations should implement immediate mitigations including disabling the vulnerable S Secure application, applying available security patches from Samsung, and educating users about the risks of leaving devices unlocked. The vulnerability also highlights the importance of proper security testing for mobile applications, particularly those with system-level access privileges, and underscores the need for robust permission model implementations that prevent unauthorized access to protected application data.