CVE-2015-9032 in Android
Summary
by MITRE
In all Android releases from CAF using the Linux kernel, a DRM key was exposed to QTEE applications.
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Analysis
by VulDB Data Team • 12/27/2020
The vulnerability identified as CVE-2015-9032 represents a critical security flaw within the Android operating system ecosystem, specifically affecting versions that utilize the Linux kernel and Qualcomm's Android Framework. This issue stems from an improper implementation of the Trusted Execution Environment (TEE) architecture where sensitive cryptographic material intended for secure processing was inadvertently exposed to applications running within the Qualcomm TrustZone Execution Environment (QTEE). The flaw manifests as a privilege escalation vulnerability that undermines the fundamental security boundaries designed to isolate sensitive operations from regular application execution contexts.
The technical root cause of this vulnerability lies in the insufficient access control mechanisms implemented within the Android security framework's interaction with the TEE subsystem. Specifically, the DRM key material that should remain protected within the secure execution environment was accessible to non-privileged QTEE applications through improper kernel-level interfaces or system call implementations. This exposure occurs at the kernel level where the boundary between trusted and untrusted execution contexts fails to maintain proper isolation, allowing malicious applications to potentially extract or manipulate the cryptographic keys used for digital rights management operations. The vulnerability affects the integrity and confidentiality guarantees that the TEE is designed to provide, creating a pathway for unauthorized access to protected content and cryptographic operations.
The operational impact of CVE-2015-9032 extends beyond simple information disclosure, as it fundamentally compromises the security model of Android devices that rely on TEE for content protection and secure transactions. Attackers exploiting this vulnerability could potentially decrypt protected media content, forge digital signatures, or manipulate secure cryptographic operations that are essential for maintaining content integrity and user privacy. The implications are particularly severe for devices that handle sensitive information or provide premium content services, as this flaw could enable widespread unauthorized access to protected digital assets and undermine the trust model that secure execution environments are designed to establish. This vulnerability directly relates to CWE-284, which addresses improper access control within security systems, and can be mapped to ATT&CK technique T1548.003 for bypassing application control mechanisms.
Mitigation strategies for CVE-2015-9032 require immediate system updates from device manufacturers and carriers, as the vulnerability exists within core kernel components that cannot be patched through standard application-level updates. Organizations should implement comprehensive device management policies that enforce timely security updates and monitor for unauthorized modifications to system components. The recommended approach involves applying the security patches provided by Qualcomm and Google that address the kernel-level access control implementations and restore proper isolation between secure and non-secure execution environments. Additionally, device administrators should consider implementing network-level monitoring to detect potential exploitation attempts and establish incident response procedures specifically tailored to address TEE-based security breaches. The vulnerability underscores the importance of maintaining proper kernel security boundaries and demonstrates how seemingly minor implementation flaws can compromise entire security architectures, particularly in environments where multiple security layers must maintain strict isolation to prevent unauthorized access to sensitive operations.