CVE-2020-0405 in Android
Summary
by MITRE
In NetworkStackNotifier, there is a possible permissions bypass due to an unsafe implicit PendingIntent. This could lead to local escalation of privilege with User execution privileges needed. User interaction is not needed for exploitation.Product: AndroidVersions: Android-11Android ID: A-157475111
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Analysis
by VulDB Data Team • 09/19/2020
The vulnerability identified as CVE-2020-0405 resides within the NetworkStackNotifier component of Android operating systems, specifically affecting Android 11 and earlier versions. This security flaw represents a critical permission bypass issue that arises from the improper handling of implicit PendingIntents within the network stack notification system. The vulnerability manifests when the system fails to properly validate or secure PendingIntent objects that are implicitly created, allowing malicious applications to potentially escalate their privileges from standard user level to elevated system privileges.
The technical root cause of this vulnerability stems from the unsafe creation and handling of implicit PendingIntents in the NetworkStackNotifier implementation. When the system creates PendingIntent objects without proper security controls or explicit intent validation, it creates an attack surface where malicious applications can exploit the implicit nature of these intents to gain unauthorized access to system resources. This flaw aligns with CWE-264, which addresses permissions, privileges, and access controls, specifically focusing on the improper handling of security-sensitive objects. The vulnerability exploits the fundamental principle that implicit intents should not be used in contexts where security boundaries are critical, as they can be manipulated by unauthorized applications.
The operational impact of this vulnerability is significant as it enables local privilege escalation attacks that require only standard user execution privileges to exploit. An attacker with a malicious application running on the device can leverage this flaw to execute code with elevated privileges, potentially gaining access to sensitive system functions, data, or even full device control. This represents a severe security risk because it allows attackers to bypass the normal Android security model where applications operate in isolated sandboxes with limited system access. The attack vector does not require user interaction, making it particularly dangerous as it can be exploited automatically without any user awareness or consent, aligning with ATT&CK technique T1068 which covers local privilege escalation through system-level vulnerabilities.
The exploitation of CVE-2020-0405 demonstrates how seemingly minor implementation flaws in system components can lead to major security compromises. The vulnerability affects the core network stack notification mechanisms that are fundamental to Android's operation, making it a critical target for attackers seeking persistent access to devices. This flaw represents a failure in the principle of least privilege where system components should not be able to create implicit intents that could be manipulated by other applications. The Android security model relies heavily on explicit intent handling and proper permission checking, but this vulnerability shows how implicit PendingIntent creation can undermine these protections. Organizations and device manufacturers should prioritize patching this vulnerability through the Android security updates, as it represents a clear pathway for attackers to escalate privileges and access sensitive system resources without requiring any special user interaction or elevated privileges beyond basic application execution. The vulnerability also highlights the importance of proper intent validation and the need for explicit security controls in system-level components that handle sensitive operations.