CVE-2015-9160 in Android
Summary
by MITRE
In Android before 2018-04-05 or earlier security patch level on Qualcomm Snapdragon Automobile, Snapdragon Mobile, and Snapdragon Wear MDM9206, MDM9607, MDM9635M, MDM9650, MSM8909W, SD 210/SD 212/SD 205, SD 400, SD 410/12, SD 425, SD 430, SD 450, SD 615/16/SD 415, SD 617, SD 625, SD 650/52, SD 800, SD 808, SD 810, SD 820, SD 820A, SD 835, SD 845, and SD 850, integer overflow may occur when values passed from HLOS (graphics driver busy time, and total time) in TZBSP_GFX_DCVS_UPDATE_ID are very large.
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Analysis
by VulDB Data Team • 01/26/2020
This vulnerability resides in the Qualcomm Snapdragon chipset family affecting Android devices prior to the 2018-04-05 security patch level. The issue manifests within the TrustZone BSP (TZBSP_GFX_DCVS_UPDATE_ID) component where integer overflow occurs during graphics driver time measurements. The flaw specifically impacts automotive, mobile, and wearable devices utilizing the affected Snapdragon chipsets including MDM9206, MDM9607, MDM9635M, MDM9650, MSM8909W, and various SD series processors from SD 210 through SD 850. The vulnerability stems from improper handling of large integer values passed from the HLOS (Host Linux Operating System) to the TrustZone environment, particularly when processing graphics driver busy time and total time measurements.
The technical implementation of this vulnerability involves a classic integer overflow condition where values exceeding the maximum representable integer range cause wraparound behavior in the TrustZone graphics driver component. This occurs when the graphics driver reports extremely large time values during performance monitoring, which are then processed without proper bounds checking in the TZBSP_GFX_DCVS_UPDATE_ID handler. The overflow creates unpredictable behavior that can be exploited to manipulate system state, potentially leading to privilege escalation or denial of service conditions. The vulnerability is categorized under CWE-191 Integer Underflow/Overflow, specifically manifesting as an integer overflow in a trusted execution environment component.
The operational impact of this vulnerability extends beyond simple system instability to potentially enable sophisticated attacks within the secure execution environment. Attackers could leverage this integer overflow to manipulate graphics driver behavior, potentially gaining elevated privileges within the TrustZone context where sensitive operations are normally isolated from the main operating system. The affected devices operate across automotive infotainment systems, mobile smartphones, and wearable devices, creating widespread exposure across multiple device categories. The vulnerability represents a critical weakness in Qualcomm's secure processing architecture, particularly concerning the graphics subsystem's integration with the TrustZone security framework. This flaw can be exploited to bypass security boundaries and potentially access sensitive system resources that should remain protected within the secure execution environment.
Mitigation strategies for this vulnerability require immediate application of the security patches released by Qualcomm and device manufacturers. Organizations should prioritize updating all affected devices to the 2018-04-05 or later security patch level, which includes fixes for the integer overflow in the TZBSP_GFX_DCVS_UPDATE_ID handler. System administrators should implement monitoring for unusual graphics driver behavior and performance metrics that could indicate exploitation attempts. Device manufacturers should conduct thorough security assessments of their TrustZone implementations and ensure proper input validation for all time measurement parameters. The vulnerability demonstrates the critical importance of secure coding practices in trusted execution environments and aligns with ATT&CK technique T1068 for local privilege escalation through kernel exploits. Additionally, implementing runtime protections such as stack canaries and address space layout randomization can provide additional defense in depth measures against exploitation attempts targeting this specific integer overflow condition.