Nearly two in three Australians trust security agencies to safely store personal data - but they have less faith in the federal government.
The latest Essential poll found 64 per cent of people backed the Australian Federal Police, ASIO and others to store information in a way that would prevent abuse - 15 points more than when last asked in October 2015.
But more than half (52 per cent) of those surveyed had little or no trust that the government would do the same.
Two-thirds also had little or no trust in telecommunication companies and internet service providers.
The poll follows revelations last week that people's Medicare card numbers were being sold on the dark web.
The Turnbull government on Monday ordered an inquiry into security of the online system, which medical professionals use up to 45,000 times a day.
Meanwhile, more than one in five Australians say they have had their credit card number stolen and 14 per cent have been the victim of online fraud - a jump from five years ago.
A third have had a virus that damaged their computer or data.
The survey of 1020 people found women were more likely than men to have been a victim of credit card theft, cyber bullying and online stalking, while men were more likely to get a computer virus or fall victim to online fraud.