Dell warned Australian customers late Wednesday that their details may have been among the millions compromised after US marketing firm, Epsilon, discovered it was hacked last week.
Epsilon was in possession of Australian customer details as Dell's global email marketing supplier.
“Whilst no credit card, banking or other personally identifiable information was involved, we felt it was important to let you know that your email address may have been accessed,” Dell Australia's consumer and small business executive director, Deborah Harrigan, explained in an email.
Customers’ first and last names may also have been compromised, she explained.
“We recommend that you do not provide any sensitive information through email, or open emails from senders you do not know. Dell will never ask for your financial information through email.”
Harrigan said Dell had informed the Australian Privacy Commissioner and the Australian Communications and Media Authority.
Dell's Australian warning came as UK department store Marks and Spencer also confirmed that its customers may have been exposed in the breach.
Epsilon had "detected" that its email system was hacked on March 31, and later clarified that 2 per cent of its clients were affected after dozens of major US brands sent notices to customers to be wary of phishing emails as a result of the breach.
McKinsey Quarterly, JP Morgan Chase, Best Buy, TiVO, Walgreens, Ritz Carlton Rewards are amongst those to have issued breach notifications.
More recent companies include Verizon, JCrew, and Victoria's Secret, according to CNN.