CVE-2016-0846 in Android
Summary
by MITRE
libs/binder/IMemory.cpp in the IMemory Native Interface in Android 4.x before 4.4.4, 5.0.x before 5.0.2, 5.1.x before 5.1.1, and 6.x before 2016-04-01 does not properly consider the heap size, which allows attackers to gain privileges via a crafted application, as demonstrated by obtaining Signature or SignatureOrSystem access, aka internal bug 26877992.
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Analysis
by VulDB Data Team • 06/07/2024
The vulnerability identified as CVE-2016-0846 resides within the Android operating system's binder driver implementation, specifically in the IMemory native interface located at libs/binder/IMemory.cpp. This flaw affects multiple Android versions including 4.x before 4.4.4, 5.0.x before 5.0.2, 5.1.x before 5.1.1, and 6.x before the specified date. The vulnerability stems from improper heap size consideration during memory allocation operations within the Android binder mechanism, which serves as the primary inter-process communication framework for the operating system. The binder driver facilitates communication between different applications and system services, making it a critical component in the Android security architecture.
The technical flaw manifests when an attacker crafts a malicious application that exploits the improper heap size handling in the IMemory interface. This vulnerability allows for privilege escalation by enabling a regular application to obtain elevated permissions that should only be available to system-level components or applications with signature-level access. The specific privilege levels that can be obtained include Signature access and SignatureOrSystem access, which grant applications the ability to access protected system resources and perform operations that would normally be restricted to system applications or those signed with platform keys. This represents a significant security weakness in the Android permission model and memory management subsystem.
The operational impact of this vulnerability is substantial as it allows attackers to bypass the normal Android security boundaries and elevate their application's privileges to system-level access. The exploit requires a crafted application that can manipulate the heap allocation behavior through the binder interface, potentially enabling malicious actors to gain unauthorized access to sensitive system functions, modify system components, or access protected data. This vulnerability directly affects the Android security model's integrity by allowing non-system applications to obtain permissions typically reserved for system applications or platform-signed components, creating potential pathways for further exploitation and system compromise.
Mitigation strategies for CVE-2016-0846 primarily involve updating affected Android versions to the patched releases that address the heap size consideration flaw in the IMemory interface. Organizations should prioritize applying the relevant security patches released by Google as part of their regular Android security updates. Additionally, implementing application sandboxing measures and monitoring for anomalous binder communication patterns can help detect potential exploitation attempts. The vulnerability aligns with CWE-122, heap-based buffer overflow, and represents a privilege escalation vector that could be categorized under ATT&CK technique T1068, "Exploitation for Privilege Escalation." System administrators should also consider implementing network-based monitoring to detect unusual inter-process communication patterns that might indicate exploitation attempts, as this vulnerability specifically targets the binder driver's memory management functionality.