Their yearlong relationship has been tumultuous from the start, with frequent break-ups and awkward family ties. Chyna, who is the mother of Kardashian's young daughter, was chastised by her ex, who posted nude photos of her on both social media platforms.
Legal experts said Kardashian is crossing the line and breaking the law.
"It's a textbook case. It's how it got its name - revenge," said Bennett Kelley with the Internet Law Center.
Kelley said without a doubt Kardashian's graphic postings of Chyna constitute revenge porn, which is illegal in 24 states, including California. It's a misdemeanor punishable by up to a year in prison.
"He clearly was acting out his spite. He was acting to destroy her in some way in using something very intimate and private," Kelley said.
Revenge porn is on the rise because people think anything goes on the internet, but the law is cracking down on offenders, according to Kelley.
Just last month, actress Mischa Barton won her revenge porn case against an ex-boyfriend who allegedly tried selling a sex tape Barton said was recorded without her knowledge. The judge ordered the explicit material not be distributed and returned to the actress.
Barton's attorney, Lisa Bloom, weighed in on Kardashian's posts in interviews and on social media.
"Attempting to slut shame the mother of his child is truly sick behavior as the law recognizes. I encourage Ms. Chyna to stand up for her rights as a woman to control which images of her own body will be made public," she said.
The buzz on social media surrounds concern for Kardashian and Chyna's daughter. #PoorDream was trending on Twitter as hundreds weighed in on her parents' feud.