The data stolen in the cyber attack on TalkTalk cannot be used on its own by criminals to plunder customer's bank accounts, the company has stated.
The telecoms company announced yesterday the attack was on its website rather than its "core systems".
It said complete credit card details were not stored on the website and could not be used for financial transactions and that account passwords had not been accessed.
In a statement it said: "We now expect the amount of financial information that may have been accessed to be materially lower than initially believed and would on its own not enable a criminal to take money from your account."
Chief executive Dido Harding also insisted customer bank details have not been compromised.
"The financial information they have on its own is not enough for them to access your bank account," she said.
But she warned customers never to give out financial details if they are contacted by phone or email by anyone asking for personal information.
Police are investigating a ransom demand sent to the telecoms giant following Wednesday's attack.
Some customers have reported money going missing from their bank accounts, but TalkTalk said there was currently no evidence anyone had been affected as a result of this week's attack.
The latest breach is the third in a spate of cyber attacks affecting TalkTalk in the last eight months.
The company has reportedly been warned before by experts about its security.
A spokesman for the firm said since previous attacks they had been working with world leading cyber security experts to make their system as secure as possible.
But he added: "Unfortunately no system is ever totally invincible - there was clearly more that should have been done in this case, and I am very sorry for the worry and frustration this attack has caused our customers."
Why are you making commenting on The Herald only available to subscribers?
It should have been a safe space for informed debate, somewhere for readers to discuss issues around the biggest stories of the day, but all too often the below the line comments on most websites have become bogged down by off-topic discussions and abuse.
heraldscotland.com is tackling this problem by allowing only subscribers to comment.
We are doing this to improve the experience for our loyal readers and we believe it will reduce the ability of trolls and troublemakers, who occasionally find their way onto our site, to abuse our journalists and readers. We also hope it will help the comments section fulfil its promise as a part of Scotland's conversation with itself.
We are lucky at The Herald. We are read by an informed, educated readership who can add their knowledge and insights to our stories.
That is invaluable.
We are making the subscriber-only change to support our valued readers, who tell us they don't want the site cluttered up with irrelevant comments, untruths and abuse.
In the past, the journalist’s job was to collect and distribute information to the audience. Technology means that readers can shape a discussion. We look forward to hearing from you on heraldscotland.com
Comments & Moderation
Readers’ comments: You are personally liable for the content of any comments you upload to this website, so please act responsibly. We do not pre-moderate or monitor readers’ comments appearing on our websites, but we do post-moderate in response to complaints we receive or otherwise when a potential problem comes to our attention. You can make a complaint by using the ‘report this post’ link . We may then apply our discretion under the user terms to amend or delete comments.
Post moderation is undertaken full-time 9am-6pm on weekdays, and on a part-time basis outwith those hours.
Read the rules here