CVE-2020-0441 in Android
Summary
by MITRE • 11/10/2020
In Message and toBundle of Notification.java, there is a possible resource exhaustion due to improper input validation. This could lead to remote denial of service requiring a device reset to fix with no additional execution privileges needed. User interaction is not needed for exploitation.Product: AndroidVersions: Android-11 Android-8.0 Android-8.1 Android-9 Android-10Android ID: A-158304295
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Analysis
by VulDB Data Team • 12/04/2020
The vulnerability identified as CVE-2020-0441 resides within the Android notification system, specifically in the Message and toBundle methods of the Notification.java file. This issue represents a classic resource exhaustion flaw that can be exploited to cause remote denial of service conditions without requiring any special execution privileges or user interaction. The vulnerability affects multiple Android versions including Android 8.0, 8.1, 9, 10, and 11, indicating it has been present across a significant portion of the Android ecosystem. The root cause stems from inadequate input validation mechanisms that fail to properly sanitize or limit the size and complexity of notification data structures during processing.
The technical flaw manifests when malicious notification data is processed through the Notification.java implementation, particularly in how the toBundle method handles message parameters. This improper validation allows attackers to craft specially formatted notifications that consume excessive system resources during processing. The vulnerability operates at the system level within Android's notification framework, making it particularly dangerous as it can be triggered through legitimate notification channels without requiring elevated privileges. The lack of user interaction requirement means this vulnerability can be exploited through automated means, potentially enabling widespread denial of service attacks across affected Android devices.
From an operational perspective, the impact of this vulnerability extends beyond simple service disruption as it can force devices into a state requiring manual reset to restore normal operation. This resource exhaustion attack vector can be particularly damaging in enterprise environments where Android devices may be used for critical operations or where multiple devices are managed centrally. The vulnerability's exploitation does not require any additional privileges, making it accessible to attackers who may only have the ability to send notifications to target devices. This characteristic aligns with the attack pattern described in the ATT&CK framework under the privilege escalation and denial of service categories, specifically targeting system-level processes that handle user-facing notifications.
The vulnerability's classification under CWE 400 indicates it represents an improper input validation issue that leads to resource exhaustion, which is a common pattern in mobile operating systems where notification handling often involves complex data structures and processing. Organizations should implement immediate mitigations including applying the latest Android security patches, implementing network-level filtering of suspicious notification traffic, and monitoring for unusual notification processing patterns. The Android security team addressed this issue through the regular security update cycle, and device manufacturers were expected to roll out patches to affected devices. Given the nature of the vulnerability and its potential for remote exploitation without user interaction, organizations should prioritize patch management and consider implementing additional network monitoring to detect potential exploitation attempts.