According to Twyford, it found "a poor approach to managing employee wellbeing and ensuring a healthy culture. This includes instances where allegations of bullying and harassment were not appropriately addressed".
The release said the new CAA board chair had apologised to staff.
CAA chief executive Graeme Harris retired earlier this month, although the Ministry of Transport would not be drawn on whether Harris' retirement was related to the review into the authority's culture
Chairman Nigel Gould also resigned last year following a request from the government.
The Public Service Association said the review into CAA management made for "tough reading".
The union said it took "sustained pressure from whistleblowers, media and unions before awareness of this toxic culture reached high enough in government for action to be taken, and a long process of reform lies ahead".
PSA national secretary Glenn Barclay said the PSA's submission to the ministerial review had pointed out that "not only have bullying and harassment been long standing problems, whistleblowers who challenged this were treated badly".