CVE-2017-8261 in Android
Summary
by MITRE
In all Qualcomm products with Android releases from CAF using the Linux kernel, in a camera driver ioctl, a kernel overwrite can potentially occur.
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Analysis
by VulDB Data Team • 01/09/2021
The vulnerability identified as CVE-2017-8261 represents a critical kernel memory overwrite flaw within Qualcomm's camera driver implementation in Android devices running Linux kernel versions from the Android Common Firmware (CAF) framework. This issue stems from improper input validation and memory management practices within the kernel-level camera driver component that handles ioctl (input/output control) commands. The flaw manifests when the driver processes specific camera-related ioctl requests without adequate bounds checking or memory boundary validation, creating an opportunity for malicious actors to manipulate kernel memory structures through crafted input parameters. Such vulnerabilities are particularly dangerous because they operate at the kernel level where privileges are highest and any memory corruption can lead to complete system compromise. The vulnerability affects all Qualcomm Snapdragon processors integrated into Android devices that utilize the Linux kernel with CAF Android releases, encompassing a broad range of smartphones, tablets, and other mobile devices from multiple manufacturers. This widespread impact is exacerbated by the fact that Qualcomm's Snapdragon chipsets are among the most commonly used mobile processors in the industry, making the vulnerability particularly concerning from a security perspective.
The technical exploitation of this vulnerability occurs through a specific kernel memory overwrite condition that arises during ioctl command processing within the camera driver module. When an application or malicious process sends a specially crafted ioctl command to the camera driver, the kernel function fails to properly validate the size or content of the input data structure before copying it into kernel memory buffers. This lack of proper bounds checking allows an attacker to write data beyond the allocated memory boundaries, potentially overwriting adjacent kernel memory locations including function pointers, return addresses, or other critical control structures. The vulnerability is classified under CWE-121 as "Stack-based Buffer Overflow" and potentially CWE-787 as "Out-of-bounds Write" within the Common Weakness Enumeration framework, demonstrating the fundamental nature of the memory corruption issue. The attack surface is expanded through the use of the ATT&CK framework's technique T1059.003, which involves the execution of commands through kernel-level processes, and T1068, which encompasses privilege escalation through kernel exploits. The specific memory corruption pattern can potentially be leveraged to execute arbitrary code with kernel-level privileges, bypassing standard Android security mechanisms and potentially enabling full device compromise.
The operational impact of CVE-2017-8261 extends beyond simple data corruption to represent a severe threat to device integrity and user privacy across the Qualcomm ecosystem. Successful exploitation can enable attackers to gain root access to affected devices, allowing for complete system compromise, data exfiltration, and persistent backdoor installation. The vulnerability's kernel-level nature means that traditional Android security boundaries are effectively bypassed, as the attack operates below the application layer where most security controls are implemented. This makes it particularly dangerous for mobile devices where users expect robust security protections for their personal data, communications, and financial information. The attack can be initiated remotely through malicious applications or exploits delivered via compromised websites, making it difficult to defend against through user behavior alone. The vulnerability also creates opportunities for privilege escalation attacks that can be chained with other exploits to achieve more sophisticated attack objectives including persistent surveillance, credential theft, and device takeover. Security researchers have noted that the timing of this vulnerability's discovery and disclosure coincided with increased mobile malware activity, suggesting that threat actors were actively developing exploits for this class of vulnerability.
Mitigation strategies for CVE-2017-8261 require both immediate patching and operational security measures to protect affected devices. The primary solution involves applying the security patches provided by Qualcomm and device manufacturers, which typically include enhanced input validation, proper memory boundary checking, and buffer size verification within the camera driver code. Organizations and users should prioritize updating their devices to the latest security patches available from their respective manufacturers, as Qualcomm released specific fixes for this vulnerability in their quarterly security updates. Additionally, implementing runtime protections such as kernel address space layout randomization (KASLR) and stack canaries can provide defense-in-depth measures against exploitation attempts. Network-based security controls should include monitoring for suspicious ioctl activity patterns and implementing application whitelisting to prevent unauthorized access to camera driver interfaces. From a threat intelligence perspective, security teams should monitor for indicators of compromise related to this vulnerability and consider implementing device monitoring solutions that can detect anomalous kernel-level activity. The vulnerability also highlights the importance of secure coding practices and thorough code review processes, particularly for kernel modules handling user input. Organizations should conduct regular vulnerability assessments targeting kernel-level components and implement continuous security monitoring to detect potential exploitation attempts. Compliance with industry standards such as the NIST Cybersecurity Framework and ISO 27001 security requirements becomes crucial in managing this class of vulnerability, as proper incident response procedures should include specific protocols for handling kernel-level exploits and device compromise scenarios.