Description

When a Tauri application uses the dialog plugin's file or folder picker, an attacker with JavaScript execution (XSS) can force the scope expansion to be recursive, granting read/write access to an entire directory tree after a single user click on a normal-looking OS file dialog. The user has no indication that recursive access was granted, and the expanded scope cannot be revoked for the lifetime of the application.

Executive Summary

Technical Details

Mitigations

References

Additional Metadata

{
  "score": "7.7",
  "pubDate": "2026-09-23T10:17:08.810Z",
  "pubdate": "2026-09-23T10:17:08.810Z",
  "executiveSummary": "A vulnerability exists in the Tauri dialog plugin where malicious JavaScript execution, such as XSS, can cause unauthorized scope expansion. This flaw allows an attacker to manipulate the file system permission model, granting the application recursive read/write access to a directory tree beyond the user's initial intention.\nThe vulnerability type is an Improper Authorization and Authorization Bypass. By triggering the file or folder picker, an attacker can influence the scope configuration, effectively elevating the privileges of the application's file system access.\nThe impact is significant, as a single user interaction with a legitimate-looking OS file dialog can result in persistent, broad access to sensitive local files for the remainder of the application's runtime. The user is provided no notification or mechanism to revoke this extended permission.\nThe primary risk lies in the silent escalation of privileges within the application sandbox. Successful exploitation requires an attacker to have already achieved arbitrary JavaScript execution within the frontend context. Once the malicious code is executing, no further authentication is required, and the exploit leverages the existing trust between the user and the legitimate OS-level dialog component.",
  "technicalDetails": "The root cause of this vulnerability lies in the insecure handling of the scope management logic within the Tauri dialog plugin. When the plugin invokes the system-level file or folder picker, it accepts parameters that define the authorized access boundaries for the application. Under normal conditions, these scopes are intended to be restrictive and specific to the file or folder selected by the user.\nThe vulnerability allows for the injection of recursive flags or configuration overrides during the dialog invocation process. An attacker who has achieved Cross-Site Scripting (XSS) in the application's frontend context can intercept or programmatically trigger the dialog plugin call. By manipulating the arguments passed to the file picker function, the attacker forces the underlying Rust-based backend to treat the selected path as a recursive scope rather than a single file or directory reference.\nThe attack flow follows a structured path. First, the attacker identifies a vulnerable entry point where user-controlled input can influence the frontend execution, leading to XSS. Second, the attacker triggers the Tauri dialog plugin's picker API. During the execution of this call, the attacker injects malicious configuration parameters—specifically those governing scope—into the payload sent to the backend process. Third, the backend, failing to sufficiently validate or constrain the requested scope parameters, propagates these malicious flags to the host operating system's file permission model.\nUpon successful execution, the application receives a broad, persistent handle to the targeted directory tree. Because this scope expansion occurs at the plugin level and is maintained by the application state, the granted access remains active for the duration of the application lifecycle. The user remains unaware that they have authorized access to a wider scope than they intended, as the dialog picker UI does not indicate the change in scope boundaries.\nPost-exploitation, the attacker possesses the capability to perform arbitrary read and write operations within the expanded scope. This access is limited only by the permissions of the user account running the Tauri application. Given the persistent nature of this scope expansion, the attacker can silently exfiltrate sensitive files, modify configuration data, or inject malicious content into the target environment without further interaction. The lack of an integrated mechanism to revoke or re-authenticate these scopes exacerbates the security risk, as the elevated privilege persists until the application process is terminated."
}