Vodafone has admitted that hackers have accessed the personal details of almost 2,000 customers.
The attack happened over the weekend, when some accounts were accessed by criminals who had acquired passwords and email addresses from "an unknown source external to Vodafone."
Vodafone has insisted (via The Guardian) in a statement that its systems "were not compromised or breached in any way."
Apparently, an attempt was made to access some customers' account details between midnight on Wednesday and midnight on Thursday. Vodafone began an investigation and notified the National Crime Agency, Ofcom and the Information Commissioner's Office on Friday night.
Vodafone insists that "our security protocols were fundamentally effective," and that it addressed the problem quickly enough that only a limited number of accounts have been breached.
"Whilst our security protocols were fundamentally effective, we know that 1,827 customers have had their accounts accessed, potentially giving the criminals involved the customer's name, their mobile telephone number, their bank sort code, the last four digits of their bank account," says Vodafone.
Apparently, no credit or debit card details were obtained in the attack, and the information that was obtained "cannot be used directly to access customers' bank accounts."
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However, Vodafone warns that those compromised by this attack are at risk of fraud and phishing attempts. The relevant accounts have been blocked and the customers informed.
The attack, while on a completely different scale of severity, comes just a week after UK broadband provider TalkTalk was hacked. It's now known that 1.2 million customer email and phone numbers and 21,000 bank details were stolen in the cyber-attack.
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