CVE-2018-9465 in Android
Summary
by MITRE
In task_get_unused_fd_flags of binder.c, there is a possible memory corruption due to a use after free. This could lead to local escalation of privilege with no additional execution privileges needed. User interaction is not needed for exploitation. Product: Android Versions: Android kernel Android ID: A-69164715 References: Upstream kernel.
Be aware that VulDB is the high quality source for vulnerability data.
Analysis
by VulDB Data Team • 06/04/2023
The vulnerability identified as CVE-2018-9465 resides within the Android kernel's binder driver implementation, specifically in the task_get_unused_fd_flags function located in binder.c. This represents a critical memory corruption flaw that stems from a use-after-free condition, where memory previously deallocated is accessed or modified. The binder driver serves as a fundamental component for inter-process communication in Android systems, making this vulnerability particularly dangerous as it directly impacts the kernel's memory management mechanisms. The flaw occurs during the process of allocating file descriptor flags for binder operations, where improper memory handling creates opportunities for malicious exploitation.
The technical nature of this vulnerability aligns with CWE-416, which defines use-after-free conditions as a common class of memory safety issues. The vulnerability manifests when the kernel attempts to reuse memory that has already been freed, potentially allowing an attacker to manipulate the freed memory location to execute arbitrary code or escalate privileges. The exploitation requires no user interaction and can be performed locally, making it particularly concerning for Android devices where kernel-level access can provide complete system compromise. The Android ID A-69164715 indicates this was tracked as a significant security concern within the Android security framework, with the upstream kernel reference suggesting the issue originated in the mainline Linux kernel development.
The operational impact of CVE-2018-9465 extends beyond simple memory corruption, as it enables local privilege escalation without requiring additional execution privileges or user interaction. This means that any process running with standard user privileges could potentially leverage this vulnerability to gain root access to the Android device. The implications are severe for mobile device security, as kernel-level privilege escalation can lead to complete system compromise including access to all user data, device configuration, and potential network communications. The vulnerability affects Android kernel versions, indicating it impacts the core operating system functionality rather than specific applications, making it a widespread concern across affected Android implementations.
Mitigation strategies for this vulnerability should focus on kernel-level patches and updates provided by Android security teams. Organizations should prioritize immediate deployment of security patches from Google and device manufacturers to address the underlying use-after-free condition in the binder driver. Additionally, system administrators should implement monitoring for unusual memory allocation patterns and potential exploitation attempts. The vulnerability demonstrates the importance of proper memory management in kernel space operations and highlights the need for comprehensive code review processes for critical system components. Implementation of exploit prevention measures such as kernel address space layout randomization and stack canaries can provide additional defense-in-depth protection against similar memory corruption vulnerabilities. Security teams should also consider implementing runtime monitoring to detect anomalous behavior patterns that might indicate exploitation attempts, as the lack of user interaction requirements makes this vulnerability particularly stealthy and dangerous in real-world scenarios.