CVE-2021-0586 in Android
Summary
by MITRE • 07/15/2021
In onCreate of DevicePickerFragment.java, there is a possible way to trick the user to select an unwanted bluetooth device due to a tapjacking/overlay attack. This could lead to local escalation of privilege with no additional execution privileges needed. User interaction is needed for exploitation.Product: AndroidVersions: Android-11 Android-8.1 Android-9 Android-10Android ID: A-182584940
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Analysis
by VulDB Data Team • 07/18/2021
The vulnerability identified as CVE-2021-0586 resides within the DevicePickerFragment.java component of Android operating systems, specifically affecting versions Android 8.1, 9, 10, and 11. This flaw represents a sophisticated user interface manipulation attack that exploits the trust users place in system dialogs during Bluetooth device pairing operations. The vulnerability manifests as a potential tapjacking or overlay attack vector that allows malicious actors to deceive users into inadvertently selecting unauthorized Bluetooth devices, fundamentally compromising the integrity of the device pairing process.
The technical implementation of this vulnerability stems from insufficient input validation and user interface security measures within the Bluetooth device selection interface. When users encounter the device picker dialog during Bluetooth pairing, an attacker can overlay malicious content that appears to be part of the legitimate interface but actually manipulates the user's selection behavior. This overlay technique exploits the lack of proper z-index management and input event handling within the Android framework, creating a scenario where user interactions are intercepted or misdirected. The flaw specifically affects the onCreate method of DevicePickerFragment.java, where the dialog presentation logic fails to adequately protect against malicious overlay attempts that could occur during the device selection process.
The operational impact of this vulnerability extends beyond simple user deception to potentially enable local privilege escalation without requiring additional malicious code execution privileges. An attacker who successfully executes this overlay attack could manipulate a user into pairing with a malicious Bluetooth device that serves as a gateway for further exploitation. This could lead to unauthorized access to the device's Bluetooth capabilities, potential data exfiltration, or establishment of persistent backdoor access points. The attack requires only user interaction to be successful, making it particularly dangerous as it leverages social engineering aspects alongside technical exploitation, aligning with attack patterns documented in the attack tree framework where user interaction serves as a critical enabling factor for privilege escalation vectors.
This vulnerability maps directly to CWE-691, which addresses insufficient protection against overlay attacks, and demonstrates characteristics consistent with the attack pattern described in the MITRE ATT&CK framework under T1056.001 - Input Injection and T1068 - Exploitation for Privilege Escalation. The security implications extend to Android's security model where the principle of least privilege is compromised when users are tricked into selecting malicious devices. The vulnerability's persistence across multiple Android versions indicates a fundamental flaw in the framework's approach to user interface security, particularly in contexts where user interaction is required for system-level operations. Organizations should consider implementing additional security controls such as user interface integrity verification mechanisms, enhanced input event validation, and proper overlay detection systems to mitigate this class of vulnerability. The remediation approach should focus on strengthening the device picker dialog's resistance to overlay attacks through improved z-index management, input event filtering, and enhanced user interface validation mechanisms.