CVE-2016-5859 in Android
Summary
by MITRE
In a sound driver in all Qualcomm products in all Android releases from CAF using the Linux kernel, if a function is called with a very large length, an integer overflow could occur followed by a buffer overflow.
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Analysis
by VulDB Data Team • 12/15/2022
The vulnerability identified as CVE-2016-5859 represents a critical security flaw within Qualcomm's sound driver implementation across all Android devices utilizing the Linux kernel framework. This issue manifests in the form of an integer overflow that subsequently leads to a buffer overflow condition, creating a significant attack surface for malicious actors. The vulnerability affects all Qualcomm products running Android releases from the Code Aurora Forum (CAF) and demonstrates the inherent risks present in kernel-level audio driver implementations that fail to properly validate input parameters.
The technical execution of this vulnerability occurs when a function receives a parameter representing a length value that exceeds the maximum representable value for the integer type being used. When this occurs, the integer overflow causes the length value to wrap around to a much smaller number, which then gets used as a buffer size parameter. This misrepresentation allows an attacker to bypass normal buffer size validation checks and subsequently write data beyond the allocated buffer boundaries. The flaw is particularly dangerous because it operates at the kernel level within the sound driver subsystem, providing potential access to critical system resources and memory spaces that should remain protected from user-space applications.
The operational impact of CVE-2016-5859 extends beyond simple buffer corruption, as it provides attackers with the capability to execute arbitrary code within the kernel context. This privilege escalation allows malicious actors to gain full control over device operations, potentially enabling data exfiltration, persistent backdoor installation, or complete system compromise. The vulnerability is particularly concerning given that it affects all Qualcomm products running Android, meaning that millions of devices across various manufacturers could be potentially compromised. The attack vector typically involves crafting malicious audio data or system calls that trigger the vulnerable function with oversized parameters, making it difficult to detect through conventional security monitoring approaches.
From a cybersecurity perspective, this vulnerability aligns with CWE-190, which specifically addresses integer overflow conditions, and CWE-121, which covers stack-based buffer overflow scenarios. The attack pattern follows established techniques documented in the MITRE ATT&CK framework under the T1068, which describes 'Exploitation for Privilege Escalation', and T1059, covering 'Command and Scripting Interpreter' methods that attackers might employ to execute malicious code. Organizations should implement immediate mitigations including kernel updates, input validation patches, and enhanced monitoring of audio-related system calls. The remediation approach requires comprehensive driver patching across all affected Qualcomm-based Android devices, with particular attention to ensuring that all parameter validation mechanisms properly handle edge cases and overflow conditions. Additionally, implementing kernel address space layout randomization and other exploit mitigation techniques can help reduce the effectiveness of potential exploitation attempts.