[BUG] [v0.0.7] list_files() in api/files.rs has no path validation, allowing traversal to arbitrary filesystem paths

[katotomoya0105]

Summary

In src/cortex-app-server/src/api/files.rs, the list_files() handler accepts an arbitrary path from the request body and reads it directly with fs::read_dir without any path validation or traversal protection. Every other mutating file operation in the same file (write_file, delete_file) correctly calls validate_path_for_write / validate_path_for_delete from path_security.rs, but list_files and read_file are missing this check entirely.

Affected Code

// src/cortex-app-server/src/api/files.rs  lines 27-87
pub async fn list_files(Json(req): Json<ListFilesRequest>) -> AppResult<Json<ListFilesResponse>> {
    use std::fs;

    let path = std::path::Path::new(&req.path);   // ← raw, unvalidated path

    if !path.exists() { ... }
    if !path.is_dir()  { ... }

    let dir_entries = fs::read_dir(path)   // ← reads arbitrary path
        .map_err(...)?;
    ...
}

Compare with write_file (line 225) which correctly validates:

let validated_path = validate_path_for_write(path).map_err(AppError::BadRequest)?;

The same omission exists in read_file (line 193) and create_directory (line 282).

Root Cause

The validate_path_safe / validate_path_for_write helpers in path_security.rs enforce that paths stay within allowed roots (home directory, /workspace, /tmp, etc.) and resolve symlinks to prevent escapes. These checks were applied to write/delete operations but were not applied to read/list operations, presumably under the assumption that reading is harmless. However, listing and reading arbitrary paths is a significant information-disclosure vulnerability.

Impact

An authenticated (or unauthenticated, depending on middleware configuration) client can:

• List the contents of /etc, /root, /proc, or any other directory on the host.
• Read the contents of sensitive files such as /etc/passwd, /etc/shadow, ~/.ssh/id_rsa, environment files, or secret stores.
• In containerised deployments, enumerate mounted secrets or service-account tokens.

Suggested Fix

Apply validate_path_safe before performing any filesystem read operation:

use super::path_security::validate_path_safe;

pub async fn list_files(Json(req): Json<ListFilesRequest>) -> AppResult<Json<ListFilesResponse>> {
    let path = std::path::Path::new(&req.path);
    let validated_path = validate_path_safe(path).map_err(AppError::BadRequest)?;

    if !validated_path.exists() { ... }
    if !validated_path.is_dir()  { ... }

    let dir_entries = fs::read_dir(&validated_path)?;
    ...
}

Apply the same fix to read_file and create_directory.