Cardiff chief executive Simon Lim criticised the transfer policies of former manager Malky Mackay and Iain Moody, the ex-head of recruitment, in a statement released on Thursday.
Lim confirmed the club effectively wrote off nearly £9million over Danish striker Cornelius, who has returned to FC Copenhagen after just seven months in Wales.
Club-record signing Cornelius failed to score in his doomed South Wales stint, and now Cardiff bosses have singled out his disastrous transfer.
"The key shareholders have made their dissatisfaction of such a huge loss known to the board of directors which they believe is due to imprudent and careless management undertaken by the previous football management," Lim said in the statement.
Cardiff's chief executive also praised new manager Ole Gunnar Solskjaer's work in the January transfer window, another veiled swipe at former boss Mackay.
"Our shareholders have expressed their support and pleasure to the new management team," the statement reads.
"Tan Sri Vincent Tan, through the board of directors and with their support, is 'encouraged by the work done by manager Ole Gunnar Solskjaer in the January transfer window.'
"Solskjaer was instrumental in attracting top professionals who have the experience and the willpower to make an immediate impact in the club's desire to maintain its Premier League status."
Lim confirmed through the statement that Cardiff spent £6million on six permanent January recruits and the loan deal for Wilfried Zaha, and recouped £3million from player sales in the same period.
"This is good business for the club, where all participants were fully informed and an integral part of a process," said Lim.
"There has been a lot of press speculation on the loss incurred by the club due to sales. This unfortunately is true.
"We took the hard decision to incur these losses for the good of the club.
"To commit the club to a significant cost and liability over a five year contract for one player is not prudent, especially as he was not to contribute to our success now, but was for the future."