The HotelHippo hotel booking site has been taken offline after a customer who is a security expert said the site's IT systems were riddled with security flaws, according to his blog post.
While trying to book accommodations Scott Helme found that he could access information about others who had previously booked through the service.
It's possible to “start walking backwards through the booking reference numbers, which are sequential, and pull out the data associated with each one,” Helme wrote, though no credit card information was made available.
Helme uncovered a SQL injection vulnerability and failures to comply with PCI standards. He also noted concerns about HTTPs configurations. Helme alerted HotelHippo to the flaws June 25, and after the BBC got involved, the company released a statement saying it was taking “urgent action” to make fixes. The Information Commissioner's Office is investigating.