The track is titled "Swish Swish," and #SquadMember Ruby Rose has already taken it upon herself to defend Taylor, calling out Katy pretty savagely on Twitter.
Taylor herself hasn't retaliated to the tune, and it looks like she doesn't need to because another one of her close friends has come out and dragged Katy.
Joseph Kahn has directed several of Taylor's music videos, including the iconic "Bad Blood," and although he also worked with Katy on "Waking Up in Vegas," he has made it clear that he is 3,000% team Taylor.
"If you're gonna do a diss track, at least put a decent hook in it," he tweeted.
It's not the first time he has publicly come to Taylor's defence. Back when the whole Taylor vs Kimye drama was happening, he tweeted, "Ain't the first time the Kardashians supported the murder of an innocent blonde woman."
As for Katy, she has just appeared in the newest installment of Carpool Karaoke with James Corden, where she revealed that she is 100% ready to squash the beef with Tay Tay... but not before she gets her revenge.