CVE-2015-3833 in Android
Summary
by MITRE
The getRunningAppProcesses function in services/core/java/com/android/server/am/ActivityManagerService.java in Android before 5.1.1 LMY48I allows attackers to bypass intended getRecentTasks restrictions and discover the name of the foreground application via a crafted application, aka internal bug 20034603.
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Analysis
by VulDB Data Team • 02/03/2018
The vulnerability identified as CVE-2015-3833 represents a significant security flaw in the Android operating system's Activity Manager Service that undermines the platform's application isolation and privacy controls. This issue affects Android versions prior to 5.1.1 LMY48I and specifically targets the getRunningAppProcesses function within the core system services. The flaw allows malicious actors to circumvent the intended restrictions that should prevent unauthorized access to information about running applications, particularly those operating in the foreground. The vulnerability stems from insufficient validation and access control mechanisms within the system's process management framework, creating an avenue for unauthorized information disclosure.
The technical implementation of this vulnerability occurs through the manipulation of the getRunningAppProcesses function in the ActivityManagerService.java file. This function is designed to provide information about currently running applications to authorized system components and legitimate applications. However, the flaw enables attackers to craft malicious applications that can bypass the normal access controls and restrictions imposed by the getRecentTasks API. The vulnerability operates by exploiting a weakness in how the system validates incoming requests for process information, allowing unauthorized applications to query and retrieve the names of foreground applications without proper authorization. This represents a direct violation of Android's security model, where applications should be restricted from accessing information about other applications without explicit permission or appropriate system-level privileges.
The operational impact of CVE-2015-3833 extends beyond simple information disclosure, as it fundamentally undermines the security boundaries that protect user privacy and application integrity. An attacker exploiting this vulnerability could gain knowledge of which applications are currently active in the foreground, potentially enabling more sophisticated attacks such as targeted phishing, malware targeting, or social engineering campaigns. The ability to discover foreground application names provides attackers with valuable context about user activities and can be leveraged to craft more convincing attacks or to identify applications that might contain sensitive data. This vulnerability particularly affects the security model's principle of least privilege, where applications should only have access to information necessary for their operation. The flaw also relates to the broader category of privilege escalation and information disclosure attacks that have been documented in the cybersecurity community.
This vulnerability aligns with several established security frameworks and threat models, particularly those related to Android's security architecture and application sandboxing mechanisms. From a CWE perspective, this issue can be categorized as a weakness in the validation of access control mechanisms, specifically related to insufficient access control validation. The vulnerability also maps to ATT&CK techniques involving credential access and reconnaissance activities, where adversaries attempt to gather information about running processes and applications to better understand the target environment. The flaw demonstrates the importance of proper input validation and access control implementation within system-level services. Security practitioners should note that this vulnerability represents a classic example of how insufficient validation in core system components can create exploitable paths that bypass higher-level security controls. The remediation for this issue required proper implementation of access control checks and validation of application permissions before allowing process information retrieval, which aligns with security best practices established in various industry standards and frameworks including those from NIST and ISO 27001. Organizations should prioritize patching this vulnerability as it represents a significant risk to user privacy and application security within the Android ecosystem.