Munger said the much-maligned pharmaceutical turned out to be a "sewer" and those who created it deserved everything they got, after the Sequoia Fund was sued by shareholders for its lofty investments on the firm.
Buffett, Berkshire's chairman and CEO, said Saturday that there were warning "patterns" at Valeant that should have been recognized. He added that several people urged them to invest in Valeant, but the business model is flawed and management lacked integrity.
Buffett also said Sequoia's investment in Valeant was "a very unfortunate period where a manager got overly entranced with a business."
Valeant declined CNBC's request for comment.
Valeant has been under pressure from regulators and investors alike. Recently, Michael Pearson left his position as Valeant's chief executive.
— CNBC's Alex Crippen and Reuters contributed to this report.