An fiesty Twitter exchange between Ms Harrison and the former Victorian premier escalated late Monday after Seven West won an interim court injunction preventing Ms Harrison from using social media to publish confidential documents.
"You have bombarded me .. with threats if I tell my story. The only thing I have taken back here is my voice. And I intend to keep using it," Ms Harrison told Mr Kennett in a tweet.
"What you do not like is being called out for being hypocrites."
Mr Kennett hit back saying "what we do not like is you releasing commercial documents that have nothing to do with you claim and is not your property."
"We have respected the confidentiality (that) SWM and Ms Harrison signed up to twice. Time to correct the record."
Ms Harrison, former executive assistant and lover to Seven West chief executive Tim Worner, has been using Twitter to leak documents in recent days to counter legal action by Seven West lawyers.
The 39 year old has been threatening to expose what she calls the "truth" about internal matters at Seven West despite Tim Worner being cleared by an internal inquiry of wrongdoing including claims of drug use and credit card fraud.
Seven West obtained an injunction from the Supreme Court of NSW to prevent Ms Harrison from releasing documents or property of the company.
"It has became clear late last week that Ms Harrison is now releasing or divulging commercial in confidence emails and other documents that she has no right to hold," Seven West Media said in a statement.
Amber Harrison has accused Seven West of an orchestrated campaign to spin the scandal of her affair with Mr Worner which was known to the Seven West board three years ago.
"Jeff, your team leaked the tale they needed to protect your CEO in March 2015 - and then blamed me for it."
With the injunction hearing scheduled for tomorrow, Mr Kennett's public comments on Twitter are seen as unusual given the high stakes nature of the case and the reputational damage already done to Seven West.
Mr Kennett, who is also chairman of the mental health initiative Beyond Blue, has become Seven West's unofficial spokesman on the case when looks certain to descend into an murky, expensive and highly personal legal battle.