13. Lamar Odom
Lamar Odom didn't just go on a drug binge. He went on a binge with his penis during an ugly run in 2013, while still married to Khloe Kardashian.
14. Rita Ora
We can't confirm this one. But Rob Kardashian says she slept with "like 20 dudes" while dating him.
15. Nick Carter
Nick Carter has admitted it: he cheated on Paris Hilton with Ashlee Simpson... a long time ago.
16. Brad Pitt
It's old news, but we know it's true: Brad Pitt did cheat on Jennifer Aniston with Angelina Jolie.
17. David Boreanaz
David Boreanaz slept with Rachel Uchitel while married. Yes, he has something in common with Tiger Woods.
18. Hank Baskett
Hank Baskett is accused of stepping out on Kendra Wilkinson. With a transgender model. While his wife was pregnant.
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