CVE-2018-9587 in Android
Summary
by MITRE
In savePhotoFromUriToUri of ContactPhotoUtils.java in Android-7.0, Android-7.1.1, Android-7.1.2, Android-8.0, Android-8.1 and Android-9, there is possible unauthorized access to files within the contact app due to a confused deputy scenario. This could lead to local escalation of privilege with no additional execution privileges needed. User interaction is needed for exploitation. Android ID: A-113597344.
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Analysis
by VulDB Data Team • 07/04/2023
The vulnerability identified as CVE-2018-9587 represents a critical security flaw in the Android operating system affecting versions 7.0 through 9.0. This issue resides within the ContactPhotoUtils.java file and specifically targets the savePhotoFromUriToUri method that handles photo processing within the contacts application. The vulnerability stems from a confused deputy scenario where the system incorrectly interprets file access permissions, creating an unauthorized access pathway that could be exploited by malicious actors to gain elevated privileges on affected devices.
The technical implementation of this vulnerability involves a flaw in the permission checking mechanism during file operations within the Android contact management system. When processing contact photos through URI-based file operations, the system fails to properly validate the originating source of the file access request. This confusion between legitimate and malicious file access requests allows an attacker to manipulate the system into performing unauthorized file operations. The vulnerability operates at the system level where the contact application's file handling logic does not adequately distinguish between authorized and unauthorized access attempts, particularly when dealing with inter-process communication scenarios.
From an operational perspective, this vulnerability presents a significant risk for privilege escalation attacks that can be executed without requiring additional execution privileges or root access. The attack requires only user interaction to be successful, making it particularly dangerous in real-world scenarios where users might unknowingly trigger the exploit through seemingly benign contact management operations. The exploitation process leverages the confused deputy pattern to redirect file operations to unintended targets, potentially allowing attackers to access sensitive contact data or modify system files with elevated privileges.
The security implications extend beyond simple unauthorized access as this vulnerability creates a persistent threat vector that could be exploited for more sophisticated attacks. Attackers could potentially use this flaw to access other applications' data, modify contact information, or even install malicious payloads that persist across system reboots. The vulnerability's classification under CWE-284 (Improper Access Control) and its alignment with ATT&CK technique T1068 (Exploitation for Privilege Escalation) demonstrates its potential for serious security consequences. Organizations and users should consider this vulnerability as a critical threat that requires immediate attention, particularly in environments where Android devices handle sensitive information or serve as part of larger enterprise security infrastructures.
Mitigation strategies for CVE-2018-9587 should include applying the latest security patches from Google, which address the confused deputy scenario by implementing proper permission validation and file access controls within the contact photo handling system. System administrators should also consider implementing additional security measures such as monitoring for unusual file access patterns, restricting contact application permissions, and conducting regular security audits of mobile device management policies. Users should avoid interacting with suspicious contact data or third-party applications that might trigger this vulnerability during normal operation. The patch implementation addresses the root cause by ensuring that URI-based file operations properly validate access permissions and prevent unauthorized file redirection that could lead to privilege escalation attacks.