Kendall and Kylie Jenner Pull All 'Vintage T-Shirts,' Apologize for Jacking Music Icon Images

Kendall and Kylie Jenner learned a valuable lesson today -- sometimes it's NOT easier to ask for forgiveness than permission ... because they just apologized for ripping off images of music icons to hawk t-shirts.

Kendall and Kylie just waived the white flag saying ... "These designs were not well thought out and we deeply apologize to anyone that has been upset and/or offended, especially to the families of the artists."

It's pretty incredible. The Jenners slapped images of Notorious B.I.G., Tupac, Ozzy Osbourne, The Doors, Pink Floyd and others ... without ever contacting them or their estates. We say incredible because they themselves have been embroiled in fights where people have tried using their images.

We broke the story ... Biggie's estate fired off a cease and desist letter to the Jenners and Biggie's mom accused them of "exploitation."

Kendall and Kylie have now scrubbed their site of the entire vintage line.