CVE-2018-11266 in Android
Summary
by MITRE
In all android releases(Android for MSM, Firefox OS for MSM, QRD Android) from CAF using the linux kernel, improper input validation can lead to an improper access to already freed up dci client entries while closing dci client.
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Analysis
by VulDB Data Team • 06/11/2023
This vulnerability exists within the linux kernel implementation used in various android platforms including MSM based devices, firefox os for msm, and qrd android systems. The issue stems from inadequate input validation mechanisms that fail to properly verify the state of dci client entries during the cleanup process. The vulnerability manifests when the system attempts to close dci client entries that have already been freed, creating a scenario where improper access occurs to memory locations that should no longer be accessible. This represents a classic use-after-free condition that can be exploited to gain unauthorized access to system resources or potentially execute arbitrary code.
The technical flaw resides in the improper handling of dci client entry management within the kernel's memory allocation and deallocation routines. When a dci client closes its connection, the system should validate that the client entry is still valid and accessible before proceeding with cleanup operations. However, the current implementation lacks proper state verification checks, allowing the system to attempt access to memory that has already been freed and potentially reallocated. This vulnerability specifically affects the linux kernel components that manage dci client connections and their lifecycle management, making it particularly dangerous in mobile environments where kernel-level access can provide extensive system control. The improper access to freed memory entries creates opportunities for attackers to manipulate system behavior through memory corruption or information disclosure.
The operational impact of this vulnerability is significant within the mobile security landscape, particularly for devices running affected android versions and kernel implementations. Attackers could potentially exploit this weakness to escalate privileges, gain unauthorized access to system resources, or cause system instability through memory corruption. The vulnerability affects multiple platform variants including android for msm, firefox os for msm, and qrd android, indicating a widespread exposure across various mobile device manufacturers. Given that these platforms are commonly used in enterprise and consumer environments, the potential for exploitation extends beyond simple denial of service to include serious security compromises. The use-after-free nature of the vulnerability aligns with common attack patterns described in the attack technique framework where adversaries leverage memory corruption to achieve system compromise.
Mitigation strategies should focus on implementing proper input validation and state verification mechanisms within the kernel's dci client management code. The primary fix involves adding comprehensive checks to ensure that dci client entries are valid and accessible before attempting any cleanup operations. System administrators should prioritize updating to kernel versions that address this vulnerability and implement proper memory management practices. The vulnerability demonstrates the importance of proper resource management and access control in kernel-level code, as outlined in common weakness enumeration standards where improper access to freed memory represents a well-documented security risk. Organizations should also consider implementing runtime monitoring and memory protection mechanisms to detect and prevent exploitation attempts. Regular security audits of kernel components and adherence to secure coding practices are essential to prevent similar vulnerabilities from emerging in future implementations.