McMahon is the husband of Linda McMahon, who heads Trump's Small Business Administration.
The doctored clip was first shared on Reddit, before being tweeted out by Trump.
In a statement on Twitter, CNN recalled comments from White House spokeswoman Sarah Huckabee Sanders last week that the president doesn't condone violence against the media.
"'The President in no way form or fashion has ever promoted or encouraged violence. If anything, quite the contrary.' - @SHSanders45 6/29/17," the CNN tweet said.
CNN's Jim Acosta immediately hit out at Trump's video, tweeting: "Isn't pro wrestling fake?"
Donald Trump Jr. retorted: "Yes, just like your coverage."
The president frequently takes aim at CNN and The New York Times, often referring to the TV network as "fake news" and the newspaper as "failing".
Three CNN staffers resigned last week after the network retracted a story linking a Trump ally to a Russian investment bank, as well as potential lay-offs at The New York Times.
It comes a day after Trump raged on Twitter that his use of social media was "modern day presidential".
The New York businessman drew broad condemnation for his Thursday tweets in which he called a female TV anchor "crazy" and saying she was "bleeding badly from a face-lift" when he saw her at his Florida estate, Mar-a-Lago.
The vicious personal attack was slammed as sexist and vulgar by many Democrats and Republicans.
Republican Ohio Governor John Kasich called Trump's tweets "unacceptable".
"We've seen this for quite a while. You know, it's unfortunate and people are now begging the president not to do this, and you know you got to stop doing it," he told America's ABC. "We'll have to see what happens. It's one of the few things that I think has brought Republicans and Democrats together."
While such tirades may not be associated with traditional standards of presidential statesmanship, Trump insists it's all part of his plan to make America great again.
Meanwhile, White House aide Sebastian Gorka has claimed that mainstream news media are losing influence, citing the CNN resignations.
"To those supporters of the Trump administration who are worried by all the fake news reporting of the last 23 weeks, I can assure you, just ignore it," Mr Gorka, who serves as deputy assistant to President Trump, said in a radio interview on Sunday,
"The fake news complex is collapsing in on itself. We see that with the massive scandal at CNN, having to fire people who were generating totally false stories about the administration. We see that with the severe personnel cuts at The New York Times."
