The federal government’s proposal to ban cyber ransom payments will expose Australian businesses to even more cyber extortion than they already face, and could put a target on the back of those organisations that might be exempt from such a ban, the head of cyber at one of Australia’s largest law firms warns.

Valeska Bloch, who runs the cyber law practice at top-tier law firm Allens, which advises many of Australia’s largest companies on the legality of paying cyber ransoms, said almost four out of five Australian victims of ransomware and data-breach extortion attacks decided to pay the ransom, often to protect the privacy of their customers.