CVE-2020-0186 in Android
Summary
by MITRE
In hal_fd_init of hal_fd.cc, there is a possible out of bounds write due to an incorrect bounds check. This could lead to local escalation of privilege with System execution privileges needed. User interaction is not needed for exploitation.Product: AndroidVersions: Android-10Android ID: A-146144463
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Analysis
by VulDB Data Team • 06/12/2020
The vulnerability identified as CVE-2020-0186 resides within the Android HAL (Hardware Abstraction Layer) component, specifically in the hal_fd_init function located in hal_fd.cc. This flaw represents a critical security issue that could potentially enable local privilege escalation attacks. The vulnerability manifests as an out-of-bounds write condition that occurs due to an incorrect bounds check implementation. The affected Android version is Android 10, with the specific Android ID A-146144463 documenting this particular weakness. The security implications are significant as exploitation of this vulnerability could allow an attacker with system execution privileges to escalate their privileges locally, potentially gaining elevated access to system resources and functionality.
The technical nature of this vulnerability stems from improper input validation within the HAL file descriptor initialization process. When the hal_fd_init function processes file descriptor operations, it fails to properly validate array bounds before performing write operations. This incorrect bounds checking creates a scenario where memory operations can extend beyond allocated buffer boundaries, resulting in unpredictable behavior and potential code execution opportunities. The flaw operates at the kernel level within the Android HAL subsystem, making it particularly dangerous as it can be leveraged to bypass standard security mechanisms. The vulnerability's classification aligns with CWE-129, which addresses "Improper Validation of Array Index," and CWE-787, which covers "Out-of-bounds Write." These weaknesses are particularly concerning in the context of Android's security architecture where proper bounds checking is essential for maintaining system integrity.
From an operational perspective, the exploitation of CVE-2020-0186 requires an attacker to already possess system execution privileges, which represents a baseline requirement for the attack vector. However, the potential impact remains severe as it enables local privilege escalation, allowing the attacker to gain elevated system-level access. The attack scenario typically involves an attacker who has already compromised a system or has access to a system with system-level privileges. The vulnerability does not require user interaction for exploitation, making it particularly dangerous as it can be triggered automatically without user involvement. This characteristic places the vulnerability within the ATT&CK framework's privilege escalation techniques, specifically targeting the "T1068 - Exploitation for Privilege Escalation" category. The potential for unauthorized system access and data compromise makes this vulnerability particularly concerning for organizations deploying Android 10 systems.
Mitigation strategies for CVE-2020-0186 should focus on immediate patch deployment as provided by Google through their regular security updates. Organizations should ensure their Android 10 devices receive the latest security patches that address this specific bounds checking flaw. Additionally, system administrators should implement comprehensive monitoring to detect any unusual system behavior that might indicate exploitation attempts. The vulnerability's nature suggests that runtime protections such as address space layout randomization and stack canaries could provide additional defense in depth. Security teams should also consider implementing application whitelisting policies and restricting system-level access to minimize potential attack surfaces. Regular security assessments and vulnerability scanning should be conducted to identify any similar issues within the Android HAL subsystem or related components. The patching process should be prioritized at the highest level given the potential for privilege escalation and the absence of user interaction requirements for exploitation.