def check_unrar(unrarLocation):
    if not unrarLocation:
        return

    if not os.path.exists(unrarLocation):
        return _('Unrar binary file not found')

    try:
        unrarLocation = [unrarLocation]
        value = process_wait(unrarLocation, pattern='UNRAR (.*) freeware')
        if value:
            version = value.group(1)
            log.debug("unrar version %s", version)

    except (OSError, UnicodeDecodeError) as err:
        log.error_or_exception(err)
        return _('Error excecuting UnRar')
The web server receives a URL or similar request from an upstream component and retrieves the contents of this URL, but it does not sufficiently ensure that the request is being sent to the expected destination.