Call of Duty: Modern Warfare and Warzone has had broken shotgun snipers before, but this is something else.
The 12-Gauge Deputy underbarrel shotgun attachment for the FR 556 assault rifle is, well, there's no nice way to say this: it's broken beyond belief. It's dishing out insane damage at a range no underbarrel shotgun should. Right now, it's a one-hit kill machine - eliminating players with full armour plates and full health at a range of 15 metres.
Clearly, this is not working as intended. With the recent launch of Season 5, developer Infinity Ward buffed the FR 556 and it hasn't worked properly. What appears to have happened is Infinity Ward's range buff for the FR 556 has carried over to the underbarrel shotgun attachment as well. High-profile Call of Duty YouTuber TheXclusiveAce released a video highlighting the issue, and of course the wider Call of Duty community picked it up.