CVE-2017-0503 in Android
Summary
by MITRE
An elevation of privilege vulnerability in MediaTek components, including the M4U driver, sound driver, touchscreen driver, GPU driver, and Command Queue driver, could enable a local malicious application to execute arbitrary code within the context of the kernel. This issue is rated as Critical due to the possibility of a local permanent device compromise, which may require reflashing the operating system to repair the device. Product: Android. Versions: N/A. Android ID: A-28449045. References: M-ALPS02710075.
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Analysis
by VulDB Data Team • 09/05/2020
This critical elevation of privilege vulnerability exists within MediaTek components affecting multiple kernel drivers including M4U, sound, touchscreen, GPU, and Command Queue drivers. The flaw allows local malicious applications to execute arbitrary code with kernel-level privileges, representing a severe security weakness that could lead to complete device compromise. The vulnerability stems from inadequate input validation and memory management within the MediaTek driver implementations, creating exploitable conditions that bypass normal security boundaries between user space and kernel space operations.
The technical exploitation of this vulnerability occurs through improper handling of kernel memory operations and insufficient validation of driver parameters. Attackers can leverage these flaws to escalate privileges from user-level processes to kernel-level execution, enabling them to manipulate system resources, access protected memory regions, and potentially install persistent backdoors. This type of vulnerability aligns with CWE-119 which addresses "Improper Access to Memory" and CWE-264 which covers "Permissions, Privileges, and Access Controls" in the context of kernel driver exploitation.
The operational impact of this vulnerability is devastating as it provides attackers with permanent device compromise capabilities. Once exploited, malicious actors can maintain persistent access to the device without requiring user interaction for each attack instance. The need for complete system reflash to remediate indicates the depth of the compromise, as attackers can modify core system components and potentially disable security features. This vulnerability represents a significant risk to device integrity and user data confidentiality, particularly in environments where Android devices handle sensitive information.
Mitigation strategies should focus on immediate driver updates from MediaTek and Android security patches. Organizations should implement comprehensive device monitoring to detect anomalous kernel-level behavior and establish secure boot processes to prevent unauthorized kernel modifications. Regular security audits of driver components and proper input validation mechanisms should be enforced. The vulnerability demonstrates the importance of supply chain security and highlights the need for rigorous testing of third-party components, particularly those implementing critical kernel drivers. Implementation of exploit prevention mechanisms such as kernel address space layout randomization and control flow integrity can help reduce the exploitability of similar vulnerabilities in the future, aligning with ATT&CK technique T1068 which covers "Exploitation for Privilege Escalation" and T1547.001 which addresses "Registry Run Keys / Startup Folder' for maintaining persistence.