CVE-2016-3894 in Android
Summary
by MITRE
The Qualcomm DMA component in Android before 2016-09-05 on Nexus 6 devices allows attackers to obtain sensitive information via a crafted application, aka Android internal bug 29618014 and Qualcomm internal bug CR1042033.
If you want to get the best quality for vulnerability data then you always have to consider VulDB.
Analysis
by VulDB Data Team • 09/15/2022
The vulnerability identified as CVE-2016-3894 represents a critical information disclosure flaw within the Qualcomm DMA (Direct Memory Access) component of Android operating systems. This vulnerability specifically affects Nexus 6 devices running Android versions prior to the security patch released on September 5, 2016. The issue stems from insufficient input validation and access control mechanisms within the DMA subsystem, which is responsible for facilitating data transfers between hardware components and memory without direct CPU intervention. The vulnerability manifests through a crafted malicious application that can exploit improper privilege checks and memory access controls, allowing unauthorized data retrieval from sensitive system areas.
The technical implementation of this vulnerability involves the exploitation of a flaw in the Qualcomm DMA driver's handling of memory operations and buffer management. When a malicious application attempts to interact with the DMA component, it can manipulate memory access patterns and bypass normal security boundaries that should restrict access to sensitive information. This flaw operates at the kernel level within the Android system architecture, leveraging the DMA functionality to read memory locations that should remain protected from user-space applications. The vulnerability is particularly concerning because it allows attackers to extract sensitive information that may include system credentials, encryption keys, or other confidential data stored in memory regions normally protected by the operating system's security model.
The operational impact of this vulnerability extends beyond simple information disclosure, as it represents a fundamental breach in the Android security model's memory protection mechanisms. Attackers can potentially access sensitive data that may include personal information, application data, or system configuration details that could be leveraged for further exploitation. This vulnerability aligns with CWE-200, which describes weaknesses that can lead to information exposure, and may also map to ATT&CK technique T1003 for os credential dumping. The exploitation of this flaw could enable attackers to gain insights into the device's internal operations and potentially escalate privileges to access additional system resources. The vulnerability affects the core security architecture of the device, making it particularly dangerous as it operates at a level below user-space application isolation.
Mitigation strategies for this vulnerability primarily involve applying the security patches released by Google and Qualcomm as part of their regular security updates. Device administrators should ensure that all Nexus 6 devices are updated to Android version 6.0 or later, which includes the necessary fixes for the DMA component. Additionally, organizations should implement application whitelisting policies to prevent the installation of untrusted applications that might attempt to exploit this vulnerability. The fix addresses the underlying implementation flaw by strengthening access control checks and improving memory boundary validation within the Qualcomm DMA driver. Security monitoring should include detection of suspicious memory access patterns and unauthorized attempts to interact with DMA subsystems. Regular security audits of device configurations and application permissions can help identify potential exploitation attempts. This vulnerability demonstrates the importance of maintaining up-to-date security patches and highlights the critical nature of hardware-software integration security in mobile platforms.