Um, RUDE!

When Kathy Griffin stopped by Lance Bass’ Sirius XM show, appropriately named “Dirty Pop,” on July 30, she pulled a major no-no — at least for those of us around in the ’90s. In this incriminating photo, Griffin is seen wearing a (gasp) Backstreet Boys shirt! The horror!

As a former *NSYNC member himself, Bass posted the photo to his Instagram, writing, “@kathygriffin gets a punch in the gut for the shirt she wore to my talk show today! @dirtypoplive”.

We’ve got three words for you, Griffin: