ICYMI: Orlando Bloom threw a punch at Justin Bieber after the pair got into a bust up at Cipriani restaurant in Ibiza last week.
Bieber made a comment about Orlando's ex-wife Miranda Kerr (saying "What's up, b****?" before adding: "She was good"). Bieber is thought to have gone on a date with her while she was still with the Pirates Of The Caribbean actor.
Moss took a moment during Riccardo Tisci's 40th birthday bash on Friday - to which every A-list celeb was invited - to give Bieber a talking to.
The Sun reports Moss took him to one side, told him to calm things down and have some more respect. Good job, Kate, good job.
A source told the newspaper: "Kate had a huge go at him and told him he needed to behave. She was giving Bieber some choice words like a teacher after the singer asked to be introduced.
"He'd gone up to say hi to her like his usual cocky self expecting her to gush over him. It was quite a slap in the face."
Kate Moss bringing Justin down a peg or two? Brilliant.
Bieber has fast become the most unpopular guy in Hollywood following the punch up, and as for Miranda? She's keeping a low profile.
LOVE KATE'S STUNNING STYLE? She's still got it, hands down. Take a look through this style file to see more looks from the iconic supermodel.