A man has pleaded guilty to assaulting disabled pensioner Alan Barnes, for whom more than £300,000 was subsequently raised in donations.
The 67-year-old's collarbone was broken when he was knocked to the ground outside his Gateshead home. An online appeal on his behalf raised £330,135.
Richard Gatiss, 25, from Gateshead, pleaded guilty to assault with intent to rob at Newcastle Crown Court.
The court heard Gatiss used legal highs and had wanted money for drugs.
He appeared via videolink from prison. He will be sentenced at a later date and Judge Paul Sloan QC, the Recorder of Newcastle, warned Gatiss jail was likely.
Details from a previous hearing at Gateshead Magistrates' Court were revealed when prosecutor Keith Laidlaw said: "Legal highs played their part in this.
"There is also possession of cannabis on his record and there is a drugs background."
Gatiss pushed Mr Barnes to the pavement outside his home in January and told him to hand over his money but his victim said he had none and Gatiss then ran off.
Northumbria Police traced Gatiss after recovering forensic evidence from Mr Barnes' jacket pocket.
'Segregated in prison'
The attack was motivated by a need for money for drugs, the previous hearing was told.
At the crown court, Jamie Adams, defending, said his client was segregated in prison because of the strong feelings his crime aroused.
"He wishes me to say at this stage that he is shocked, horrified and deeply ashamed of what he did," Mr Adams said.
"He has not stopped thinking about Mr Barnes since this awful deed.
"He is very conscious of being in the public eye and everyone not just gazing at him but glaring at him.
"It is having a deleterious effect on his wellbeing.
"Necessarily, he is segregated in prison because of the way people feel about him."
Danny Savage, North of England Correspondent
Alan Barnes is the vulnerable pensioner from Gateshead who was overwhelmed by the kindness of strangers.
The 67-year-old is easily noticed. He is well known in the area where he lives. He has a range of physical disabilties because his mother contracted German Measles when she was pregnant with him.
When one local woman heard what had happened to the 4ft 6in gentleman who lived near her, she did something about it.
Katie Cutler set up an online appeal to raise £500. The appeal went viral and in a matter of days the total raised reached £330,000. The two of them first met and hugged in front of reporters - surely one of the most heartwarming images of the year so far.
Richard Gatiss cut a sorry figure when he appeared before magistrates. He sat weeping in the dock as the court was told his DNA linked him to the assault.
Newcastle Crown Court heard today that Gatiss is "shocked, horrified and deeply ashamed of what he did". He is also conscious of being in the public eye the judge was told.
Moved by Mr Barnes's plight, an online appeal to raise £500 was set up by Gateshead beautician Katie Cutler.
It attracted donations from across the globe and quickly passed the initial target.
Mr Barnes was presented with the cheque earlier this month and described it as "absolutely like a fairy story".
He intends to use the money to buy a new home as he does not want to return to the area where he was attacked.