CVE-2017-7368 in Android
Summary
by MITRE
In all Android releases from CAF using the Linux kernel, a race condition potentially exists in the ioctl handler of a sound driver.
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Analysis
by VulDB Data Team • 12/27/2020
The vulnerability identified as CVE-2017-7368 represents a critical race condition flaw within the Linux kernel implementation of Android devices, specifically affecting all Android releases that utilize the Code Aurora Forum (CAF) kernel. This issue manifests within the ioctl handler of a sound driver component, which serves as a crucial interface for controlling audio hardware through device-specific commands. The race condition occurs when multiple processes or threads attempt to access the same audio driver resources simultaneously, creating a temporal window where system state can become inconsistent or corrupted.
The technical exploitation of this vulnerability stems from improper synchronization mechanisms within the sound driver's ioctl handler implementation. When concurrent access occurs during ioctl operations, the kernel fails to properly enforce mutual exclusion, allowing for simultaneous modification of shared data structures or hardware registers. This condition can lead to memory corruption, privilege escalation, or arbitrary code execution within the kernel context. The flaw falls under CWE-362, which specifically addresses race conditions in software implementations where multiple threads or processes access shared resources without proper synchronization. The vulnerability's impact is amplified by the fact that sound drivers typically operate with elevated privileges, making successful exploitation potentially catastrophic for system integrity.
From an operational perspective, this vulnerability presents significant risks to Android device security and stability. Attackers could leverage the race condition to execute malicious code with kernel-level privileges, potentially leading to complete system compromise, data theft, or persistent backdoor installation. The nature of the flaw makes it particularly dangerous because it operates at the kernel level where standard user-space protections are ineffective. This vulnerability aligns with ATT&CK technique T1068, which covers 'Exploitation for Privilege Escalation' by providing an entry point for attackers to gain elevated system privileges. The attack surface extends to any Android device running affected kernel versions, including smartphones, tablets, and other mobile devices that utilize the CAF kernel implementation.
Mitigation strategies for CVE-2017-7368 require immediate patching of affected Android devices through official security updates from device manufacturers. System administrators and security teams should prioritize deployment of kernel-level patches that implement proper synchronization mechanisms within the sound driver's ioctl handler. The fix typically involves adding mutex locks or other concurrency control primitives to ensure exclusive access to shared resources during ioctl operations. Additionally, organizations should conduct thorough vulnerability assessments to identify devices running affected kernel versions and implement network monitoring to detect potential exploitation attempts. The remediation process must account for the complexity of Android's layered architecture, ensuring that patches do not introduce regressions in audio functionality while effectively addressing the race condition vulnerability. Regular security updates and proactive monitoring remain essential for maintaining device security posture against similar kernel-level vulnerabilities.