Hacker Exposes Private Twitter Documents

Twitter, which is generally quite private about its business plans, has fallen prey to an attack by a hacker who has apparently exposed confidential corporate information.

The hacker claims to have private documents including confidential contracts with Nokia, Samsung, Dell, AOL and Microsoft; the resumes of people who have applied to work at Twitter; personal information about Twitter employees including credit card numbers; future business plans; and floor plans and security codes for Twitter’s offices.

The breach occurred in May, but on Wednesday, the hacker, who calls himself “Hacker Croll,” leaked a large number of documents unearthed in the attack to TechCrunch and a French blog called Korben. TechCrunch said it received 310 documents.

One internal document the hacker claims to have includes projections that Twitter will have 25 million users this year, 100 million next year and 350 million in 2011, and will eventually become the first Web service to have 1 billion users.

The hacker apparently broke into the Internet accounts of various Twitter employees, including Evan Williams, Twitter’s chief executive, as well as Mr. Williams’s wife, who does not work for Twitter, and two Twitter employees. He claims to have accessed Google Apps, Gmail, PayPal, Amazon, Apple, AT&T and MobileMe accounts.