CVE-2020-0477 in Android
Summary
by MITRE • 12/15/2020
In sendLinkConfigurationChangedBroadcast of ClientModeImpl.java, there is a possible information disclosure due to a missing permission check. This could lead to local information disclosure of the current network configuration with no additional execution privileges needed. User interaction is not needed for exploitation.Product: AndroidVersions: Android-11Android ID: A-162246414
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Analysis
by VulDB Data Team • 12/18/2020
The vulnerability identified as CVE-2020-0477 resides within the Android operating system's wireless networking implementation, specifically in the ClientModeImpl.java component that manages client network connections. This flaw represents a critical security oversight that allows unauthorized information disclosure through improper permission validation mechanisms. The vulnerability manifests in the sendLinkConfigurationChangedBroadcast method where the system fails to verify appropriate authorization before broadcasting sensitive network configuration details. The issue affects Android 11 systems and is catalogued under Android ID A-162246414, indicating its significance within the Android security framework.
The technical root cause of this vulnerability stems from a missing permission check that should validate whether the calling process has appropriate authorization to access or broadcast network configuration information. According to CWE-284, this represents an improper access control vulnerability where insufficient permission validation allows unauthorized access to sensitive system resources. The flaw operates at the system level where network configuration data flows through broadcast mechanisms without proper authorization verification, creating a pathway for information disclosure attacks. This type of vulnerability falls under the ATT&CK technique T1082 for system information discovery, as it enables adversaries to extract network configuration details that could be used for further exploitation.
The operational impact of CVE-2020-0477 is significant as it enables local information disclosure without requiring any additional privileges or user interaction for exploitation. An attacker with local access to an affected Android device can extract current network configuration data including network parameters, connection settings, and potentially sensitive routing information. This information disclosure could facilitate subsequent attacks such as network reconnaissance, man-in-the-middle attacks, or targeted exploitation of network services. The vulnerability's severity is amplified by its accessibility through local processes that do not require elevated privileges, making it particularly dangerous in environments where local application execution is possible. The lack of user interaction requirements means that exploitation can occur automatically when network configuration changes occur, providing attackers with continuous access to sensitive information.
Mitigation strategies for this vulnerability should focus on implementing proper permission validation mechanisms within the sendLinkConfigurationChangedBroadcast method and similar broadcast operations throughout the Android framework. System administrators and device manufacturers should ensure that all network configuration broadcast operations include appropriate authorization checks before disseminating sensitive information. The Android security team should implement mandatory permission verification for all system-level network configuration broadcasts, aligning with security best practices outlined in the Android Security Model. Additionally, regular security audits should examine all broadcast mechanisms within the system to identify and remediate similar permission validation gaps. Device manufacturers should prioritize applying security patches that address the missing permission checks and consider implementing additional monitoring for unauthorized network configuration access attempts. The vulnerability highlights the importance of maintaining strict access controls in system-level operations and demonstrates how seemingly minor permission oversights can create significant information disclosure risks.