CVE-2017-18136 in Android
Summary
by MITRE
In Android before security patch level 2018-04-05 on Qualcomm Snapdragon Automobile, Snapdragon Mobile, and Snapdragon Wear MDM9206, MDM9607, MDM9615, MDM9635M, MDM9640, MDM9650, MSM8909W, SD 210/SD 212/SD 205, SD 400, SD 425, SD 430, SD 450, SD 615/16/SD 415, SD 617, SD 625, SD 650/52, SD 808, SD 820, SD 820A, SD 835, SD 845, in the omx aac component, a Use After Free condition may potentially occur.
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Analysis
by VulDB Data Team • 01/24/2020
The vulnerability identified as CVE-2017-18136 represents a critical use after free condition within the openMAX (OMX) AAC audio component of Qualcomm Snapdragon automotive, mobile, and wearable platforms. This flaw exists in Android systems prior to the security patch level of 2018-04-05 and affects a wide range of Qualcomm chipsets including MDM9206, MDM9607, MDM9615, MDM9635M, MDM9640, MDM9650, MSM8909W, and numerous SD series processors. The vulnerability stems from improper memory management within the multimedia framework where freed memory blocks are still referenced or accessed by subsequent operations, creating potential exploitation vectors for malicious actors.
The technical implementation of this vulnerability involves the OMX AAC component which handles Advanced Audio Coding format processing in mobile and automotive devices. When processing certain malformed audio streams or specific sequence of operations, the component fails to properly manage memory allocation and deallocation cycles. This results in a situation where memory that has been freed from the heap is subsequently accessed or reused, allowing attackers to manipulate program execution flow. The flaw operates at the intersection of multimedia processing and memory management, making it particularly dangerous as it can be triggered through standard audio playback operations.
From an operational perspective, this vulnerability poses significant risks to automotive infotainment systems and mobile devices running affected Qualcomm chipsets. Attackers could potentially exploit this condition to execute arbitrary code on the affected devices, potentially leading to complete system compromise. The vulnerability is particularly concerning in automotive environments where Snapdragon automotive platforms are deployed, as it could enable remote code execution attacks that might affect vehicle safety systems. The widespread deployment of affected chipsets across multiple device categories increases the potential attack surface significantly.
The vulnerability aligns with CWE-416 which specifically addresses use after free conditions in memory management, and represents a classic example of improper resource management in multimedia frameworks. From an attacker's perspective, this flaw maps to several ATT&CK techniques including privilege escalation and code injection, as successful exploitation could lead to full system compromise. The exploitability of this vulnerability is enhanced by the fact that it can be triggered through normal audio processing operations, making it difficult to detect and prevent through traditional security measures.
Mitigation strategies should prioritize immediate deployment of the relevant security patches released by Qualcomm and Android vendors, specifically targeting the security patch level 2018-04-05 or later. Organizations should implement comprehensive device inventory management to identify all affected platforms and prioritize patch deployment based on risk assessment. Network-based detection measures can be implemented to monitor for unusual audio processing patterns that might indicate exploitation attempts. Additionally, device manufacturers should consider implementing memory safety enhancements and runtime protections such as address space layout randomization and stack canaries to reduce the effectiveness of potential exploitation attempts. Regular security assessments and vulnerability scanning should be conducted to ensure continued protection against similar memory management flaws.