CVE-2018-21081 in Samsung
Summary
by MITRE
An issue was discovered on Samsung mobile devices with N(7.x) software. In Dual Messenger, the second app can use the runtime permissions of the first app without a user's consent. The Samsung ID is SVE-2017-11018 (March 2018).
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Analysis
by VulDB Data Team • 10/07/2020
This vulnerability exists within Samsung's Dual Messenger implementation on Android 7.x devices, representing a significant privilege escalation flaw that undermines the fundamental security model of mobile operating systems. The issue stems from improper permission handling within the dual messaging framework where secondary applications can inherit and utilize the runtime permissions granted to primary applications without explicit user consent. This creates a scenario where malicious actors could exploit the trust relationship between applications to gain unauthorized access to sensitive resources and data. The vulnerability specifically affects Samsung devices running Android Nougat version 7.x and demonstrates a failure in the permission isolation mechanisms that should protect user privacy and system security.
The technical flaw manifests through the improper implementation of Android's permission system within Samsung's proprietary Dual Messenger feature. When users install a second application through the dual messenger framework, the system fails to properly enforce permission boundaries between the primary and secondary applications. This allows the secondary application to access resources and perform actions that should require explicit user consent based on the permissions granted to the primary application. The vulnerability operates at the application runtime level, exploiting the trust relationship between applications that share the same package identifier or user context. According to CWE classification, this represents a weakness in permission management and privilege escalation, specifically CWE-276, which deals with improper privileges and access control mechanisms.
The operational impact of this vulnerability extends beyond simple privacy concerns to encompass potential data breaches and unauthorized system access. Attackers could leverage this flaw to access sensitive information such as contacts, messages, location data, and other personal information that the primary application has permission to access. The vulnerability undermines the core security principle of least privilege, allowing secondary applications to perform actions that would normally require explicit user consent. This creates a pathway for persistent threats to establish footholds within the device ecosystem, potentially enabling more sophisticated attacks including data exfiltration, surveillance, and lateral movement within the device's application environment. The attack surface is particularly concerning given that many users rely on dual messenger applications for both personal and professional communications, making the potential data exposure significant.
Mitigation strategies should focus on both immediate device-level protections and long-term architectural improvements. Users should immediately disable the Dual Messenger feature on affected devices and ensure their Samsung devices are updated to the latest security patches released by Samsung. System administrators should monitor for potential exploitation attempts and consider implementing network-based detection measures to identify unusual permission requests from dual messenger applications. The vulnerability highlights the importance of proper permission isolation and the need for third-party applications to undergo rigorous security testing before deployment. Organizations should also consider implementing mobile device management solutions that can enforce stricter permission controls and monitor application behavior for suspicious activities. From an ATT&CK framework perspective, this vulnerability maps to privilege escalation techniques and can be used as a persistence mechanism in broader attack chains. The incident underscores the necessity for comprehensive security testing of proprietary features and the critical importance of maintaining up-to-date security patches to protect against known vulnerabilities.