Shining a low-powered laser into these voice-activated systems allows attackers to inject commands of their choice from as far away as 360 feet (110m). Because voice-controlled systems often don't require users to authenticate themselves, the attack can frequently be carried out without the need of a password or PIN. Even when the system require authentication for certain actions, it may be feasible to brute force the PIN, since many devices don't limit the number of guesses a user can make. Among other things, light-based commands can be sent from one building to another and penetrate glass when a vulnerable device is kept near a closed window.
The researches carried out attacks in moderately realistic conditions and were able to control voice assistants. This is not good since, these voice assistants can then be used to control smart home devices, which include door locks, garage doors, among many others.
Hopefully, there will be a way to mitigate this attack because of the seriousness of what could happen if it were carried out.