CVE-2020-0337 in Android
Summary
by MITRE
In MediaProvider, there is a possible bypass of a permissions check due to a confused deputy. This could lead to local information disclosure, with User execution privileges needed. User interaction is not needed for exploitation.Product: AndroidVersions: Android-11Android ID: A-124329382
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Analysis
by VulDB Data Team • 09/18/2020
The vulnerability identified as CVE-2020-0337 resides within the MediaProvider component of Android operating systems, specifically affecting Android 11 and earlier versions. This flaw represents a sophisticated permissions bypass that exploits a confused deputy scenario, where a legitimate system component is manipulated to perform unauthorized actions. The vulnerability stems from improper validation of caller credentials within the media content management subsystem, creating a pathway for malicious actors to access protected media resources without proper authorization.
The technical implementation of this vulnerability involves a confused deputy problem where the MediaProvider service fails to properly authenticate the actual entity making requests to access media content. This occurs when the system incorrectly trusts the identity of a calling process that has been compromised or manipulated, allowing unauthorized access to media files stored within the device. The flaw specifically affects the permission checking mechanisms that should normally validate whether an application has adequate privileges to access specific media content, particularly in contexts where the system is processing requests from multiple potential sources.
From an operational perspective, this vulnerability enables local information disclosure attacks where an attacker with user execution privileges can potentially access media files that should normally be restricted. The impact extends beyond simple data exposure as it could provide access to sensitive personal information, including photos, videos, and audio recordings that users expect to remain private. The attack vector requires only local execution privileges, meaning that malicious applications or processes running with user-level permissions can exploit this flaw to gain unauthorized access to media content stored on the device.
The security implications of CVE-2020-0337 align with CWE-284, which addresses improper access control issues, and can be mapped to ATT&CK technique T1059 for privilege escalation and T1074 for data staging. This vulnerability demonstrates how seemingly isolated permission checking failures can create significant security gaps in mobile operating systems, particularly in components that handle sensitive user data. The exploitability of this vulnerability is enhanced by the fact that it requires minimal user interaction, making it particularly dangerous in environments where malicious applications might be installed or where privilege escalation occurs through other means.
Mitigation strategies for this vulnerability should focus on implementing robust caller identity verification within the MediaProvider component, ensuring that all requests are properly authenticated regardless of the calling process. System updates and patches should enforce stricter permission validation, particularly for operations involving media content access. Security researchers recommend implementing additional layers of verification that can detect and prevent confused deputy scenarios, including enhanced logging and monitoring of media access requests to identify anomalous patterns that might indicate exploitation attempts. Organizations should prioritize immediate patch deployment and consider implementing additional security controls to monitor for unauthorized media access patterns on affected devices.