The tweet compelled Walter Shaub, former director of the independent Office of Government Ethics, to again break a self-imposed holiday Twitter hiatus to admonish the President. Shaub resigned from his post in July amid clashes with the White House, and he has since been an outspoken critic of Trump on social media.
"The wannabe autocrat just retweeted an image depicting CNN's blood on the sole of his shoe," Shaub tweeted today. "These colicky tweets reveal he's hurting this weekend. They make him (and our country) look weak."
Joe Walsh, a conservative radio host and former Republican congressman from Illinois, also criticised Trump for attacking CNN - and the FBI.
"Mr President, put your phone down. It's Christmas. Quit attacking people on Twitter," Walsh tweeted. "Grow up sir. Have you no sense of decency? Go spend time with your family."
CNN anchor Jake Tapper noted Trump's tweet with a simple observation: "CNN-labelled blood on the sole of his shoe. Retweeted by the President of the United States on Christmas Eve."
In response to Tapper, Jason Osborne, a former Trump campaign adviser, defended the image and accused Tapper of "(making) everything about your network."
The image was of a bug because it "clearly has eyes," Osborne insisted. He also argued that Trump may not have noticed the CNN logo at the bottom of his shoe and retweeted the picture because he liked the way he looked in it.
Tapper replied: "The President retweeted an image of blood labelled 'CNN' on the sole of his shoe. I noted it. Trump Adviser now faults *me* for 'making this about' CNN. God bless us, everyone."
Trump has had a contentious relationship with the press since his campaign, regularly lashing out at certain media outlets - even individual journalists - and accusing many publications and news stations of being "fake news." CNN has regularly been the subject of Trump's attacks, on Twitter and in speeches. Earlier this month, after CNN apologised for mistakenly reporting the timing of a WikiLeaks-related email, Trump used the error as an opportunity to attack the network again.
"CNN apologised just a little while ago," Trump said at a rally in Pensacola, Florida. "They apologised. Oh, thank you, CNN. Thank you so much. You should've been apologising for the last two years."
The latest tweet was not the first time that Trump has shared a doctored image on Twitter, particularly related to CNN. In July - just before Independence Day - Trump tweeted an edited video clip that showed him slamming a man with "CNN" superimposed on his head to the ground. In the video, Trump then throws punches at the man's head, before walking away.
Trump appended the tweet with two hashtags: "#FraudNewsCNN" and "#FNN."
In September, a few days after the racially charged unrest in Charlottesville, Virginia, where a car ploughed into counterprotesters rallying against white nationalists and killed a woman, Trump retweeted an image of a train running over a CNN reporter. "Fake news can't stop the Trump train," the image read. It was later removed from Trump's account.
