CVE-2021-0491 in Android
Summary
by MITRE • 06/11/2021
In memory management driver, there is a possible escalation of privilege due to a missing permission 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-183461315
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Analysis
by VulDB Data Team • 06/14/2021
The vulnerability identified as CVE-2021-0491 resides within the memory management driver component of Android operating systems, representing a critical security flaw that enables local privilege escalation without requiring additional execution privileges or user interaction. This issue affects Android SoC implementations and has been assigned the Android ID A-183461315, indicating its severity and impact on the platform's security model. The vulnerability stems from a missing permission check within the memory management driver, which is a fundamental component responsible for handling memory allocation, deallocation, and access control within the system's kernel space.
The technical flaw manifests as an insufficient validation mechanism that fails to properly verify the privileges of processes attempting to interact with memory management functions. This missing permission check creates a pathway for malicious local processes to exploit the system's memory management subsystem and elevate their privileges from standard user level to root access. The vulnerability operates at the kernel level where memory management operations are performed, making it particularly dangerous as it can be leveraged to bypass the normal security boundaries that separate user space from kernel space. The absence of proper authorization checks means that any process running on the device can potentially manipulate memory management functions that should only be accessible to privileged system components.
The operational impact of this vulnerability is significant as it allows attackers to gain complete control over the affected Android device without requiring any additional privileges or user interaction. This means that even a simple local application could exploit this weakness to obtain root access, potentially enabling full device compromise including data theft, persistent backdoor installation, and complete system control. The lack of user interaction requirement makes this vulnerability particularly concerning as it can be exploited automatically without any manual intervention from the victim, turning it into a serious threat for both individual users and enterprise environments where Android devices are deployed. The vulnerability affects the core memory management functionality, which is utilized by virtually all system processes and applications, amplifying its potential impact.
Mitigation strategies for CVE-2021-0491 should focus on implementing proper permission checking mechanisms within the memory management driver and ensuring that all memory management operations are properly validated against the requesting process's privileges. System administrators and device manufacturers should prioritize applying the latest security patches and updates provided by Google and device vendors to address this vulnerability. The fix typically involves adding proper access control checks that validate whether the requesting process has the necessary permissions before allowing memory management operations to proceed. This vulnerability aligns with CWE-284, which describes improper access control issues in software systems, and can be mapped to ATT&CK technique T1068, which covers 'Exploitation for Privilege Escalation' in cybersecurity frameworks. Organizations should also consider implementing runtime monitoring and anomaly detection systems to identify potential exploitation attempts of this type of vulnerability, as the attack surface extends to any process that might attempt unauthorized memory management operations.