THOUSANDS of Coast computer users could find themselves without internet access after 2pm today unless they remove a secretly installed piece of malicious software.
A piece of malware known as a "Domain Name System Changer" or "DNSChanger" has been secretly installed by hackers, allowing them to control the DNS - the system which lets users access the internet and send email.
In November last year, the United States FBI worked with the Internet Systems Consortium to set up a temporary solution for those infected with DNSChanger, enabling them to continue to access internet services.
The agreement was extended in March but will finally expire today at 2pm AEST.
Coast internet users have until then to check their computer for the malware and remove it.
Owner of Coast computer firm Buzz a Geek Chris Edwards said the potential problem would be inconvenient but not catastrophic.
"There isn't a great threat. There won't be a complete meltdown of the internet," he said.
"There are already tools on the internet that can be useful for checking if a computer has this malware."
Mr Edwards said the malware was more than likely to have been downloaded unknowingly as part of free software found online.
"They embed programs which change the way the internet works on that computer."
Australian Media and Communications Authority eSecurity manager Bruce Matthews said internet users who failed to remove the malware before the deadline would have to seek technical assistance.
"This is a world-wide phenomenon and will affect internet users globally," Mr Matthews said.
He said the DNSChanger threat was a timely reminder for Australian internet users to protect themselves from malware and adopt safe internet practices.
- Visit www.dns-ok.gov.au. If the website detects that you are infected by DNSChanger or using the rogue settings, you will see a red banner warning "You appear to be affected by DNSChanger".
- You will then be able to access remediation tools and advice on the steps you can take to return your computer to normal operation and restore correct settings.