CVE-2021-0492 in Android
Summary
by MITRE • 06/11/2021
In memory management driver, there is a possible out of bounds write due to a missing bounds check. This could lead to local escalation of privilege with no additional execution privileges needed. User interaction is not needed for exploitation.Product: AndroidVersions: Android SoCAndroid ID: A-183459078
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Analysis
by VulDB Data Team • 06/18/2021
The vulnerability identified as CVE-2021-0492 resides within the memory management driver component of Android operating systems, specifically affecting Android SoC implementations. This issue represents a critical security flaw that manifests as an out-of-bounds write condition, where the system fails to perform adequate bounds checking on memory operations. The vulnerability is classified under CWE-787, which specifically addresses out-of-bounds write conditions in software systems. The memory management driver serves as a fundamental component responsible for handling memory allocation and deallocation processes, making it a prime target for privilege escalation attacks.
The technical flaw stems from the absence of proper validation mechanisms within the memory management driver's code implementation. When processing memory operations, the driver does not validate array indices or buffer boundaries before writing data, creating a scenario where malicious code can write beyond allocated memory regions. This missing bounds check allows an attacker to overwrite adjacent memory locations, potentially corrupting critical system data structures or executing arbitrary code. The vulnerability is particularly concerning because it operates at a low system level within the kernel space, where memory management operations occur with elevated privileges.
The operational impact of CVE-2021-0492 extends significantly beyond typical memory corruption issues due to its potential for local privilege escalation. An attacker with local access to the device can exploit this vulnerability without requiring additional execution privileges or user interaction, making it particularly dangerous in environments where physical access is possible. The attack vector is simplified by the fact that no user interaction is required for exploitation, meaning that an attacker could potentially compromise a device simply by having local access. This scenario aligns with ATT&CK technique T1068, which covers 'Local Privilege Escalation' through the exploitation of system vulnerabilities. The vulnerability affects Android SoC implementations and is identified by Android ID A-183459078, indicating a specific hardware-software integration issue.
Mitigation strategies for CVE-2021-0492 should focus on implementing comprehensive bounds checking mechanisms within the memory management driver code. System administrators and device manufacturers should prioritize applying security patches provided by Google and chipset vendors to address the underlying memory management flaw. The recommended approach includes strengthening code review processes to ensure all memory operations include proper bounds validation, implementing runtime memory protection mechanisms such as stack canaries, and employing address space layout randomization to complicate exploitation attempts. Additionally, security researchers should monitor for potential variations or similar vulnerabilities in related memory management components, as this flaw may indicate broader issues within the system's memory handling architecture. Organizations should also consider implementing network segmentation and access controls to limit potential attack vectors, while maintaining continuous vulnerability assessment programs to identify and remediate similar issues before they can be exploited by malicious actors.