Multiple reports since the election have claimed Mrs Clinton was the victim of a Vladimir Putin-orchestrated cyber attack.
Speaking to Russian state-funded channel RT, Mr Kiriakou was adamant the person responsible for Mrs Clinton’s failings was the former Secretary of State herself.
“The truth of the matter, and I say this with a heavy heart because I’m a lifelong Democrat… is that Hillary Clinton was a terrible candidate,” he said.
“The evidence shows that Hillary Clinton essentially stole the nomination from Bernie Sanders.
Mr Kiriakou was critical of various US intelligence agencies for handing the matter over to analysts “in the absence of facts” who made “analytical conclusions based on the bits and pieces that they are able to collect”.
He said: “We have something that has been massaged by the CIA analysts and they have drawn analytical conclusions based on what little evidence they have.
“If this hacking actually took place, there would be an electronic trail back to the point of origin. We haven’t seen any electronic trail.
Mr Kiriakou then suggested the NSA’s silence on the matter lead him to believe “the evidence doesn’t exist”.
“In fact, if you look at this report that the Democratic Party issued, the evidence is not overwhelming,” he said.
“That, coupled with the fact that the Democrats did not allow the FBI access to the server, just makes me think that there’s nothing behind the story.”