BT is being investigated by the UK’s data authority after a whistleblower claimed the company “exposed user credentials en masse”.
BT is moving seven million customers to its new email service, away from Yahoo.
It is understood that vulnerabilities were discovered while the new email system was in its testing phase last year, and that the telecoms firm was confident no personal data had been compromised.
BT confirmed the ICO had contacted them, on Thursday, to begin enquiries following the whistleblower’s remarks.
In confidential documents obtained by The Register, and confirmed by the BBC to be genuine, the ICO said: “On the basis of the information [the whistleblower] provided, we consider it unlikely that BT has complied with the requirements of the [Data Protection Act].
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