CVE-2015-9036 in Android
Summary
by MITRE
In all Qualcomm products with Android releases from CAF using the Linux kernel, an incorrect length is used to clear a memory buffer resulting in adjacent memory getting corrupted.
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Analysis
by VulDB Data Team • 11/08/2019
The vulnerability identified as CVE-2015-9036 represents a critical memory corruption flaw affecting Qualcomm products that utilize Android-based systems with Linux kernel implementations. This issue stems from improper memory management practices within the kernel-level components that Qualcomm integrates into their mobile platform solutions. The flaw manifests when the system attempts to clear a memory buffer, where an incorrect length parameter is supplied to the memory clearing function, leading to unintended memory regions being overwritten. This particular vulnerability impacts all Qualcomm products that incorporate Android releases from the Code Aurora Forum (CAF) and utilize the Linux kernel as their underlying operating system framework.
The technical root cause of this vulnerability lies in the improper handling of memory buffer operations within kernel space code, specifically when executing memory clearing routines. When the kernel attempts to zero out or clear a memory buffer for security or initialization purposes, it passes an incorrect length value to the underlying memory clearing function. This incorrect length parameter causes the clearing operation to extend beyond the intended buffer boundaries, resulting in adjacent memory locations being overwritten with zeros or other unintended data patterns. The flaw is particularly concerning because it operates at the kernel level where memory corruption can lead to privilege escalation, system instability, or potential remote code execution depending on the specific implementation details and attack surface. This type of vulnerability aligns with CWE-121, which describes stack-based buffer overflow conditions, and CWE-122, which covers heap-based buffer overflow scenarios, though the specific nature here involves improper memory clearing rather than traditional buffer overflow conditions.
The operational impact of CVE-2015-9036 extends beyond simple memory corruption, as it can potentially enable attackers to manipulate system behavior through carefully crafted inputs that trigger the vulnerable memory clearing operation. Mobile devices running affected Qualcomm platforms become susceptible to various attack vectors where adversaries could exploit this flaw to gain unauthorized access to system resources, potentially escalating privileges from user-level processes to kernel-level operations. The vulnerability affects the fundamental security posture of Qualcomm-based Android devices, as memory corruption at kernel level can compromise the entire system integrity. Attackers who can control the parameters passed to the vulnerable memory clearing function may be able to overwrite critical system data structures, function pointers, or other sensitive memory regions, leading to arbitrary code execution or system crashes that could be exploited for persistent access or data exfiltration. This vulnerability particularly impacts the ATT&CK technique T1068, which involves local privilege escalation, and T1059, covering command and scripting interpreters, as the memory corruption could enable attackers to manipulate system processes and execute malicious code with elevated privileges.
Mitigation strategies for CVE-2015-9036 require immediate attention from device manufacturers and system administrators, as the vulnerability exists within the core kernel components of affected Qualcomm platforms. The primary recommended approach involves applying firmware updates from Qualcomm that correct the memory clearing implementation by ensuring proper length parameters are used when clearing memory buffers. Organizations should prioritize patching affected devices through official update channels, as Qualcomm released specific security patches addressing this issue in their kernel implementations. Additionally, system administrators should implement monitoring solutions to detect anomalous memory access patterns that might indicate exploitation attempts, while also conducting thorough vulnerability assessments to identify any custom implementations that might contain similar memory handling flaws. The vulnerability highlights the importance of proper memory management practices in kernel code development, emphasizing the need for comprehensive code reviews and static analysis tools to identify similar issues in other memory handling functions. Security teams should also consider implementing runtime protections such as stack canaries, address space layout randomization, and other exploit mitigation techniques to reduce the effectiveness of potential exploitation attempts, though these measures are secondary to the fundamental patching required to address the root cause of the vulnerability.