Cops have nabbed a homeless man who randomly slashed a stranger on a ritzy East Village street corner, police said Sunday.

Steven Johnson, 35, was charged with attempted murder and assault in the terrifying, unprovoked Thursday attack by the Astor Place Cube.

The 30-year-old victim was standing on the corner of Astor Place and Lafayette St. around 5:20 p.m. when Johnson crept up behind him, cops said.

The attacker slashed the man in the back of the neck with an unidentified sharp object, authorities added.

The victim was taken to Bellevue Hospital, where he survived the attack.

“There was nothing going on, no altercation. Suddenly, he was down on the ground holding his neck,” witness Michael Picadi, 25, told the Daily News after the attack. “He was in the fetal position in a huge pool of blood.”

Police arrested Johnson for the attack Saturday night. His last address was a Midtown Manhattan homeless shelter, according to police.

The man’s arraignment in Manhattan Criminal Court was pending Sunday afternoon.