HSBC’s websites across the world have been hit by one of the largest cyber attacks to strike a bank in an attack that left millions of customers without access to online services.

An unknown group launched a so-called “denial of service” attack on Britain’s largest bank on Thursday evening, crashing web-based services for about seven hours. At its peak, HSBC was deluged with internet traffic 500 times its normal level, five times higher than the amount of traffic that hit the bank in a similar attack earlier this year. A spokesman for the bank said full internet services were restored by 3am yesterday and claimed that no customer data had been compromised as a result of the attack.

“We are co-operating with the relevant authorities and will co-operate with other organisations that have been similarly affected by such criminal acts,” HSBC said. “We apologise for any inconvenience caused to our customers throughout the world.”

US financial group Capital 1 is also understood to have been hit by a similar denial of service attack at the same time as HSBC.....Read more here: Millions affected after cyber attack on HSBC - Telegraph