It didn't work properly during Auckland's big storm earlier this month and now the malfunctioning Vector outage app is mistakenly revealing its customers' personal information.
Everything from customers' names and phone numbers to their email and physical addresses has been leaked by the app, according to Stuff.
The Auckland-based electricity network provider came under heavy criticism for its response to the storm on Tuesday April 10 that knocked over power lines and cut power to thousands of households.
The app failed to perform then and hasn't functioned properly since.
Now it's been revealed that the software - which is meant to let users report and follow up on Vector's work to restore power - has made the customer info it gathers available to anyone who downloads the app, Stuff reports.
Vector's app records the name, email and GPS position relating to unresolved outages reported to it, and that personal data is easily accessible to anyone who knows their way around a computer.
A Vector spokesperson told Stuff the company is deeply sorry for the data breach and it's completely rebuilding the app, while the breach will be reported to the Privacy Commissioner.
Since the leak was revealed, loading the app shows a 'server issue'. However it is still available for download through Google Play and the iTunes App Store.