A costume website described the 15-year-old Holocaust victim as "a young girl" who had "nothing but a diary and hope."
"Nazi salutes are indefensible," a CNN spokesperson said.
Jeffrey Lord, a CNN contributor and supporter of President Donald Trump, has made bigoted and sexist comments on air, like calling Trump the "Martin Luther King of Healthcare," but it was a tweet that got him fired.
The same congressman who declared war between "Christendom" and suspected Islamic terrorists used the site to further his political agenda regarding homeland security.
Spicer's repeated offensive statements "have exposed a serious gap in your knowledge of the Holocaust, its impact, and the lessons we can learn from it," the ADL told the White House spokesman.
Following White House press secretary Sean Spicer's spreading of "alternative facts" about the Holocaust, the Anti-Defamation League has offered to provide him with a little education.