CVE-2026-45521 in Android
Summary
by MITRE • 09/08/2026
In openFile of AppFuseBridge.java, there is a possible information disclosure due to a missing permission check. This could lead to local information disclosure with no additional execution privileges needed. User interaction is not needed for exploitation.
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Analysis
by VulDB Data Team • 09/09/2026
The vulnerability identified in the openFile method within AppFuseBridge.java represents a critical flaw rooted in insufficient access control mechanisms, specifically categorized under CWE-200 as an Information Exposure through sensitive data leakage or missing permission checks. This defect allows any local application on the device to interact with the bridge component without verifying whether the calling process possesses the necessary privileges to perform file operations. In Android architecture, such bridges often serve as intermediaries between native code and Java-based applications, facilitating complex interactions that require elevated system-level access. When a developer fails to enforce permission validation before executing sensitive I/O operations like opening files, they inadvertently create an attack vector where unprivileged processes can read or manipulate data intended for privileged contexts only.
From a technical perspective, the absence of a check against Android's standard permissions framework means that any application installed on the device can invoke this method directly. Since no additional execution privileges are required and user interaction is not needed, the exploitation complexity is minimal. An attacker with local access to the system could craft a malicious application or script that calls openFile repeatedly or targets specific sensitive files stored in directories accessible via this bridge. This bypasses the standard sandboxing protections intended to isolate applications from one another and from core system data. The flaw essentially treats all callers as trusted entities, violating the principle of least privilege which dictates that components should only have access to resources necessary for their function.
The operational impact of this vulnerability is significant due to its potential for local information disclosure. Attackers can potentially exfiltrate sensitive user data such as authentication tokens, personal identifiers, or proprietary application state stored in files accessible through the bridge. Because the exploitation does not require physical proximity beyond network reachability if remote components are involved, nor does it need social engineering tactics like clicking a link, the risk of automated scanning and mass exploitation is elevated. This aligns with ATT&CK technique T1005 (Data from Local System), where adversaries seek to gather data directly from compromised endpoints without triggering alarms associated with more aggressive intrusion methods. The lack of user interaction further exacerbates the severity as victims remain unaware that their data is being accessed in the background.
Mitigation strategies must focus on implementing robust access control checks within the openFile method before any file system operations are initiated. Developers should verify that the calling application holds specific permissions defined by Android, such as READ_EXTERNAL_STORAGE or custom app-specific permissions declared in the manifest and granted at runtime. Additionally, integrating strict input validation to ensure that requested file paths do not traverse outside intended directories can prevent path traversal attacks often associated with information disclosure flaws. It is also advisable to adopt a defense-in-depth approach by logging access attempts for security monitoring purposes and regularly auditing third-party libraries or bridge components for similar oversights in permission handling logic.