CVE-2021-0401 in Android
Summary
by MITRE • 02/27/2021
In vow, there is a possible memory corruption due to a race condition. This could lead to local escalation of privilege with System execution privileges needed. User interaction is needed for exploitation. Product: Android; Versions: Android-10, Android-11; Patch ID: ALPS05418265.
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Analysis
by VulDB Data Team • 03/05/2021
The vulnerability identified as CVE-2021-0401 affects the Android operating system and resides within the vow component, which represents a critical memory management subsystem. This issue manifests as a race condition that can potentially lead to memory corruption, creating a pathway for privilege escalation attacks. The vulnerability specifically impacts Android versions 10 and 11, making it a widespread concern across multiple Android releases that were prevalent during the affected period. The patch identifier ALPS05418265 indicates this was addressed within the Android Linux kernel subsystem, suggesting the flaw originated from low-level memory management operations.
The technical flaw stems from a race condition occurring within the vow component where concurrent access to shared memory resources creates a scenario where memory corruption can occur. This race condition typically arises when multiple threads or processes attempt to access and modify the same memory location simultaneously without proper synchronization mechanisms. The vulnerability is particularly dangerous because it requires system execution privileges for exploitation, meaning an attacker must already have some level of access to the system before leveraging this flaw. However, the local nature of the vulnerability means that exploitation can occur from within the device's own environment rather than requiring network-based attack vectors.
From an operational impact perspective, this vulnerability represents a significant security risk as it enables local privilege escalation, potentially allowing an attacker to gain system-level privileges from a lower-privileged account. The requirement for user interaction suggests that social engineering or pre-existing access through other means would be necessary to initiate exploitation, but once triggered, the memory corruption could provide a foothold for more extensive system compromise. The fact that this affects Android 10 and 11 versions indicates that a substantial portion of devices in the field were potentially vulnerable, particularly as these versions were widely deployed across various device manufacturers. The vulnerability aligns with CWE-362, which describes race conditions that can lead to security vulnerabilities, and could potentially map to ATT&CK technique T1068, which involves exploiting local privilege escalation opportunities.
The mitigation strategy for this vulnerability involves applying the Android security patch referenced by ALPS05418265, which would address the underlying race condition in the vow component. Device manufacturers and users should prioritize updating to patched versions of Android 10 and 11 to eliminate this memory corruption pathway. Security teams should monitor for any exploitation attempts related to this vulnerability and ensure that all devices within their environment receive the appropriate updates. Additionally, system administrators should consider implementing additional security controls such as memory protection mechanisms and process isolation to reduce the potential impact should the vulnerability be exploited. The patch likely includes proper synchronization mechanisms to prevent the concurrent access patterns that lead to the race condition, thereby eliminating the memory corruption that enables privilege escalation.