The 48-year-old was attacked in Wolston prison, with authorities confirming he had sustained minor injuries.
According to reports, Cowan suffered superficial wounds to his neck and ear when a fellow prisoner attacked him with an 'improvised implement', Queensland Corrective Services said.
Corrective Services said in a statement: 'A prisoner suffered superficial wounds to his neck and ear when he was assaulted by another prisoner in a common area of...Wolston Correctional Centre on Friday.'
'The prisoner did not sustain any serious injury.
'Queensland Corrective Services officers brought the situation quickly under control. No officers were injured.'
'There was no blood,' a Queensland Corrective Services spokesman further told Daily Mail.
It is not the first time Cowan had been the target of an attack behind bars.
In August 2016, he was scalded with boiling water when a fellow inmate tipped a bucket over him.
This article originally appeared on New Idea.