McCabe was famously fired by the FBI on March 16, 2018, after a Justice Department inspector general's report found he had repeatedly misstated his involvement in a leak to The Wall Street Journal regarding an FBI investigation into the Clinton Foundation. The watchdog office referred the matter to the U.S. Attorney's Office in Washington, which has been investigating.
Trump blasted the network on Twitter while retweeting a message by Rep. Jim Jordan, R-Ohio, who also condemned the CNN move.
"Disgraceful!" Trump simply tweeted.
The president then mocked CNN in reaction to a tweet that pointed out that CNN's highest-rated show on Wednesday was "Cuomo Prime Time," which ranked at only No. 27, with around 1 million viewers.
Meanwhile, Fox News dominated the list with four shows in the top five, including "Hannity" and "Tucker Carlson Tonight," both drawing more than 3 million viewers.
"Such a sad and pathetic fall for @CNN and Jeff Z[ucker]!" Trump said about the network and its president.
CNN's newest hire was widely panned by media critics and Twitter users.
“His credibility is non-existent," The Hill media reporter Joe Concha told Fox News. "This is truly a disservice to CNN viewers, which will only further plunge the network's credibility into a black hole.”
Fox News' Brian Flood contributed to this report.