Australian supermarket chain Woolworths canceled and re-issued more than $1.3 million (AU) worth of e-gift cards, following an email blunder that revealed the details of thousands of customers and exposed codes for nearly 8,000 shopping vouchers.

On Sunday, Woolworths told Mashable Australia in a statement that on Saturday, the company was “alerted to a technical fault with an e-gift card offered to customers.”

Fairfax Media, which initially reported on the incident, obtained a copy of the Woolworths email that was mistakenly sent out. After purchasing gift cards via Groupon, customers were supposed to receive an email from Woolworths containing their voucher information, but instead, a PDF attachment was sent, which linked to thousands of voucher codes.

The email, which also reportedly contained the names and email addresses of customers, was delivered erroneously to more than 1,000 individuals, Fairfax Media said.