I know this scenario is extremely unlikely and will probably never occur, bit I am still curious. Say, overtime starts and Team A receives the ball first. They end up kicking a field goal and the ball goes to Team B. Team B then throws an interception to Team A. For whatever reason, on the interception return, the returner gets tackled in the end zone for a safety. What would then happen after that? Would Team B get another possession?
Team A would win the game in this scenario by one point. The safety counts but the game is over because Team B had a full possession.
The NFL rulebook states:
If the second team loses possession by an interception or fumble, the down will be permitted to run to its conclusion, but if the second team’s possession has legally ended with the fumble recovery or interception, any subsequent action will not affect the outcome of the game. (If the change of possession occurs in the second team’s end zone, the score counts.)