[Kazoo2U]

Those are rubber which gets extruded during the tire vulcanization process. No danger at all.

 

[racoon]

Normal on a new tire.

 

[yst]

Have you ever seen new tires before? All have that spikes. And all have a strong rubber smell when new.

 

[Dave J]

curb feelers ,LOL

 

[crv383]

If one looked a little closer, I’d bet the other 3 tires have rubber spikes also.

 

[williamsji]

Everyone has already answered correctly.. so I will just add.. if they bother you... you can always take time out of your busy day to trim each and every one of them off the tire.

 

[crv383]

There's just as many spikes on the backside of a tire, don't forget to trim them.

 

[Wildcat]

There's just as many spikes on the backside of a tire, don't forget to trim them.

Um, you first... ?

(Pictures OP going out with the utility knife underneath the car to trim them all off... ?)