The Rainbow Six website outlines an updated code of conduct for Rainbow Six Siege, establishing a zero tolerance policy for cheating in the multiplayer first-person shooter. They say violators will be permanently banned after a first offense:

The presence of cheating in the game is something we take very seriously, and is a priority on the development team. This update is one step among many that we are working on to better engage with the community on this issue.

UPDATED CODE OF CONDUCT SECTION:

Cheating/Modding/Hacking: Player is running a modified or otherwise unauthorized version of the game client or a third party software which provides any sort of unfair advantage (wallhacks, aimhacks…) or causing detriment to other players’ experience: Maximum penalty is permanent ban on first offense.

For more information on this update to the Code of Conduct, and how Permanent Bans will work, please see this FAQ.