Hackers have again sought to transfer money collected by users of the ACT's container deposit scheme, in a repeat of an incident just over a year ago.
Users were on Thursday told a security breach had affected some express account holders in the ACT's container deposit scheme, which pays 10 cents for every eligible container returned.
"Unknown and unauthorised persons have tried to access customer accounts and transfer Express account balances to another bank account," Return-It, the company which runs the scheme, told account holders.
"Our system is set up to alert customers of changes to account details and because those customers contacted us, we were able to stop the fraudulent activity. All affected customers have already been contacted directly and no further suspicious activity has been identified."
Return-It advised customers of a similar security breach in January 2023.
The company on Thursday said it was running increased monitoring and cyber security processes as well as investigating unusual system data.
"Security policies were strengthened in January 2023 including stricter password requirements, reduced password attempts before lockout, and forced password changes for all users. Customers who have updated their password since 21 January 2023, have been protected by these improved security policies," the company's email to users said.
"We take customer Express Account security very seriously and continue to support the highest standards and best practice in cyber security."
Nicole Lawder, the opposition spokeswoman on city services, said it was unfortunate the scheme had suffered another data breach.
"Customers rightly expect high levels of security when money and personal details are concerned. I hope the ACT government does everything possible to strengthen security in the future," Ms Lawder said in a statement.
"After last year's breach, the government assured us that tighter security was on the way, yet here we are again."
Ms Lawder said the scheme needed to make Canberrans feel confident and reassured their personal details were protected.
The ACT government has been contacted for comment.
A 2021 independent analysis found the scheme would leave the ACT $40 million better off over the next 20 years due to reduced landfill costs, avoided street sweeping costs and lower processing and transport costs.
