OpenHarness prior to commit 166fcfe contains an improper access control vulnerability in built-in file tools due to inconsistent parameter handling in permission enforcement, allowing attackers who can influence agent tool execution to read arbitrary local files outside the intended repository scope. Attackers can exploit the path parameter not being passed to the PermissionChecker in read_file, write_file, edit_file, and notebook_edit tools to bypass deny rules and access sensitive files such as configuration files, credentials, and SSH material, or create and overwrite files in restricted host paths in full_auto mode.