Zendesk Hacker Accesses Twitter, Tumblr and Pinterest Data

Another day, another hack. The email addresses of Twitter, Tumblr and Pinterest users were accessed this week after a hacker got unauthorized access to Zendesk, which helps companies manage their customer-service requests.

No passwords were involved in the attack, said the companies, who are alerting their users tonight.

Zendesk CEO Mikkel Svane disclosed the security breach in a blog post on Thursday. Twitter, Tumblr and Pinterest then alerted affected users via email.

The identities of the affected companies were published by Wired, and they each have independently confirmed to AllThingsD via email, though Zendesk declined to identify them directly.

In addition to users’ email addresses, associated subject lines of the three social media companies’ support emails were compromised. Tumblr warned users that because subject lines could include their blog addresses, hackers may be able to associate their emails with their blogs.

A Zendesk spokeswoman said to expect more detail soon, while a Pinterest spokesman noted, “There is an ongoing investigation by authorities.”

San Francisco-based Zendesk is used by some 25,000 companies. Other customers include Sony Music, Disney, Vodafone, Groupon and Kickstarter.