TalkTalk Data Breach 23.10.15
Police are investigating a "significant and sustained cyber-attack" on the TalkTalk website, the UK company says.
The phone and broadband provider, which has over four million UK customers, said banking details and personal information could have been accessed.
TalkTalk said potentially all customers could be affected but it was too early to know what data had been stolen.
The Metropolitan Police said no-one had been arrested over Wednesday's attack but enquiries were ongoing.
TalkTalk said in a statement that a criminal investigation had been launched on Thursday.
It said there was a chance that some of the following customer data, not all of which was encrypted, had been accessed:
- Names and addresses
- Dates of birth
- Email addresses
- Telephone numbers
- TalkTalk account information
- Credit card and bank details
Dido Harding, chief executive of the TalkTalk group, told BBC News its website was now secure again and TV, broadband, mobile and phone services had not been affected by the attack.
By Rory Cellan-Jones, BBC technology correspondent
Cyber-attacks on consumer companies happen with mounting frequency, but TalkTalk's speedy decision to warn all of its customers that their vital data is at risk suggests that this one is very serious indeed.
We are being told that this was what's called a DDoS - a distributed denial of service attack - where a website is hit by waves of traffic so intense that it cannot cope. What is not clear is why this would result in the loss of data rather than just the site going down. One suggestion is that the DDoS was a means of distracting TalkTalk's defence team while the criminals went about their work.
I'm assured that TalkTalk customers' details, including banking information, were all being held in the UK rather than in some overseas data centre. What is less clear is the extent to which that data was encrypted.
For TalkTalk, the cost to its reputation is likely to be very serious. Now it is going to have to reassure its customers that its security practices are robust enough to regain their trust.
'Crime of our generation'
The TalkTalk sales website and the "My account" services are still down but the company hopes to restore them on Friday.
Ms Harding added: "We brought down all our websites [on Wednesday] lunchtime and have spent the last 24 hours investigating with the Met Police.
"It's too early to know exactly what data has been attacked and what has been stolen.
"Potentially it could affect all of our customers, which is why we are contacting them all by email and we will also write to them as well."
It is the third cyber attack to affect TalkTalk customers over the past 12 months.
In August, the company revealed its mobile sales site had been targeted and personal data breached.
And in February, TalkTalk customers were warned about scammers who had managed to steal thousands of account numbers and names.
Ms Harding said: "Unfortunately cybercrime is the crime of our generation. Can our defences be stronger? Absolutely. Can every company's defences be stronger?
"I'm a customer myself of Talk Talk, I've been a victim of this attack."
It is expected to take some time to contact everyone and some customers have expressed anger and frustration that they are yet to hear anything.
One customer told BBC Radio 5 live: "It's just the latest in a long line of failures... To hear about it up to 48 hours after something may have happened really isn't good enough."
Another said: "I only heard about it because I happened to turn the TV on. It is very worrying."
TalkTalk urged customers to keep an eye on their accounts over the next few months and report any unusual activity to their bank and Action Fraud on 0300 123 2040.
The company said it had contacted the major banks asking them to look out for any suspicious activity on customers' accounts. It added that every customer would be getting a year's free credit monitoring.
Ms Harding said: "The biggest risk is that customers' details have been stolen and criminals try to impersonate them."
Professor Peter Sommer, an expert an cyber security, said TalkTalk's rapid growth could be to blame for the breaches.
"They are acquiring more customers and each of those customers wants to do more things and so they have to increase their capacity... but that's an expensive exercise," he told the BBC.
"The quality and quantity of attacks increases all the time so it's a significant problem for many companies.
"But undoubtedly TalkTalk has had significant problems for some time and they simply had to go public now because personal data is available and the Information Commissioner is going to be hard down on them to see why they haven't performed better."
Story supplied by http://www.bbc.co.uk/news/uk-34611857
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