CVE-2021-1019 in Android
Summary
by MITRE • 12/15/2021
In snoozeNotification of NotificationListenerService.java, there is a possible permission confusion due to a misleading user consent dialog. This could lead to local escalation of privilege with User execution privileges needed. User interaction is needed for exploitation.Product: AndroidVersions: Android-12Android ID: A-195031401
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Analysis
by VulDB Data Team • 12/22/2021
The vulnerability identified as CVE-2021-1019 resides within the NotificationListenerService implementation in Android's system services, specifically affecting the snoozeNotification method within NotificationListenerService.java. This flaw represents a critical permission confusion issue that exploits a misleading user consent dialog mechanism, creating an exploitable condition for privilege escalation. The vulnerability affects Android 12 systems and is tracked under Android ID A-195031401, demonstrating how seemingly benign notification handling functionality can become a gateway for significant security breaches.
The technical root cause of this vulnerability stems from improper permission validation within the notification listener service framework. When users interact with notification snooze functionality, the system presents a consent dialog that misleadingly indicates the scope of permissions being requested. This dialog does not accurately represent the actual permissions that are granted, creating a confusion that malicious applications can exploit to gain elevated privileges. The flaw operates at the system level where notification handling services are designed to provide contextual awareness to users while maintaining proper permission boundaries. However, the misleading dialog creates a scenario where users unknowingly grant broader permissions than they intend, enabling unauthorized access to system resources that should remain restricted.
The operational impact of this vulnerability is severe as it enables local privilege escalation requiring only user interaction to exploit. An attacker can craft a malicious application that appears legitimate in its permission requests but actually leverages the permission confusion to gain elevated privileges within the Android system. This escalation occurs without requiring any special privileges from the attacker beyond having a user execute the malicious application. The vulnerability creates a persistent threat vector where legitimate notification handling functionality becomes a backdoor for system compromise, as the user consent process fails to accurately communicate the actual scope of permissions being requested.
This vulnerability aligns with CWE-284, which addresses improper access control, and maps to ATT&CK technique T1068, which covers local privilege escalation. The permission confusion aspect directly relates to CWE-693, which covers protection mechanism failures, while the user interaction requirement places it within the ATT&CK framework's category of techniques requiring user engagement for exploitation. The flaw demonstrates how user interface elements designed for security can become security mechanisms themselves when they fail to accurately represent the underlying system behavior. Organizations should implement immediate mitigations including updating to patched Android versions, reviewing notification permission policies, and educating users about the importance of carefully reviewing permission requests. The vulnerability also highlights the need for better sandboxing of system services and more transparent permission communication mechanisms that accurately reflect the actual access levels being granted to applications.