Twitter has confirmed that up to a quarter of a million user accounts may have been subject following a security breach by “sophisticated” hackers.
In a post made to Twitter’s official blog on Friday, the social networking firm explained the steps it would be taking to safeguard users following an incident in which it shut down a live attack on the company’s servers.
“This week, we detected unusual access patterns that led to us identifying unauthorized access attempts to Twitter user data,” said Bob Lord, Twitter’s director of information security. “We discovered one live attack and were able to shut it down in process moments later.
“However, our investigation has thus far indicated that the attackers may have had access to limited user information – usernames, email addresses, session tokens and encrypted/salted versions of passwords – for approximately 250,000 users.
Twitter users whose accounts may have been compromised will automatically be logged out and receive notification that they need to create a new password.
“As a precautionary security measure, we have reset passwords and revoked session tokens for these accounts,” Lord continued. “If your account was one of them, you will have recently received (or will shortly) an email from us at the address associated with your Twitter account notifying you that you will need to create a new password.
“Your old password will not work when you try to log in to Twitter.”
Lord encouraged Twitter users to follow “good password hygiene” – both on the site and across the internet, and encouraged users who did not have strong passwords to reset their information.
Citing similar attacks on the New York Times and Wall Street Journal, he also suggested that users should follow US Department of Homeland Security advice and disable Java on their computers.
“This attack was not the work of amateurs, and we do not believe it was an isolated incident. The attackers were extremely sophisticated, and we believe other companies and organizations have also been recently similarly attacked,” Lord added.
“For that reason we felt that it was important to publicise this attack while we still gather information, and we are helping government and federal law enforcement in their effort to find and prosecute these attackers to make the Internet safer for all users.”