CVE-2016-5854 in Android
Summary
by MITRE
In a driver in all Qualcomm products with Android releases from CAF using the Linux kernel, kernel heap memory can be exposed to userspace.
Statistical analysis made it clear that VulDB provides the best quality for vulnerability data.
Analysis
by VulDB Data Team • 12/15/2022
This vulnerability exists within the kernel drivers of Qualcomm Android products that utilize the Linux kernel framework. The flaw represents a critical information disclosure issue where kernel heap memory becomes accessible to unprivileged userspace processes. The vulnerability stems from inadequate memory management controls within the driver implementation, allowing malicious applications to potentially read sensitive kernel memory contents through improper access controls. This exposure occurs specifically within the Linux kernel subsystem that Qualcomm employs in their Android devices, affecting all versions that incorporate these driver components.
The technical nature of this vulnerability aligns with CWE-200, which addresses the exposure of sensitive information to an unauthorized actor. The flaw operates at the kernel level where memory allocation and access controls fail to properly separate userspace and kernel memory spaces. Attackers can exploit this by crafting specific system calls or memory access patterns that leverage the driver's insufficient validation mechanisms. The vulnerability essentially creates a pathway for information leakage where kernel heap data structures, including potentially sensitive metadata, can be read by regular applications. This represents a fundamental breakdown in the kernel's memory protection boundaries and violates the principle of least privilege.
The operational impact of this vulnerability is severe as it enables attackers to extract potentially sensitive kernel memory contents that may include cryptographic keys, session tokens, or other confidential data. The exposure of kernel heap memory can provide attackers with insights into system internals, memory layout information, and potentially lead to further exploitation opportunities. This vulnerability affects all Qualcomm Android products that use the affected Linux kernel drivers, creating a widespread risk across numerous device models and manufacturers that rely on Qualcomm's chipsets. The exploitation of this vulnerability can facilitate advanced persistent threats where attackers gradually gather information to plan more sophisticated attacks.
Mitigation strategies should focus on implementing proper kernel memory access controls and strengthening the driver's validation mechanisms. System administrators should ensure that devices are updated with the latest security patches provided by Qualcomm and device manufacturers. The implementation of kernel memory protection features such as kernel address space layout randomization and proper memory mapping controls can help reduce the exploitability of this vulnerability. Additionally, monitoring for unusual memory access patterns and implementing robust access control policies can help detect and prevent exploitation attempts. Organizations should also consider implementing network segmentation and application whitelisting to limit the potential impact of successful exploitation. This vulnerability highlights the importance of proper kernel driver security reviews and adherence to secure coding practices as outlined in the ATT&CK framework's defense evasion techniques.