CBS says the 39-year-old reporter "suffered a brutal and sustained sexual assault and beating."
The savage assault occurred when Logan was "surrounded by a dangerous element amidst the celebration."
"In the crush of the mob she was separated from her crew...it was a mob of more than 200 people whipped into a frenzy," a network statement said.
She was rescued by a group of women and 20 Egyptian soldiers.
Logan was flown back to the United States on the first flight the next morning.
"She is currently in the hospital recovering," a CBS spokesman said.
Several American journalists have found themselves in harm's way while reporting from the front line of the Egyptian revolution.
CNN's Anderson Cooper was set upon by a violent mob and CBS anchor Katie Couric was hassled by an angry mob, as was Christiane Amanpour.