Perth firms phreaked by VoIP hackers

Western Australia Police has warned the state's businesses to change passwords and cap international calls on enterprise VoIP (Voice over Internet Protocol) networks, afterwards investigating several cases of scammers hacking the networks to commit fraud.

The WA Police said three businesses have reported their VoIP networks hacked by opportunists using the networks to make calls to international numbers offering premium voice services - often owned by the attacker.

"Many businesses have only the most basic security in place just as factory default access pins or passwords and as such they are easy pickings for criminals," the WA Police said in a statement.

Senior Constable Paul Litherland of the Research Crime Investigation Unit warned businesses to "remain in the extreme vigilant" to ensure attempts to attack their online telecommunications networks are unsuccessful, as the Police are relatively powerless to prevent the fraud.