Zendesk, a provider of help desk service and customer service portals, was hit by a cyber attack earlier last week, the company said, with the breach possibly having compromised some Twitter, Tumblr and Pinterest data.
The security breach was revealed by the company in a blog post on Friday, and even though it did not specifically name the three social networks as victims, subsequent email alerts from Tumblr, Twitter and Pinterest to their respective users confirmed that these services were hit as well.
"We recently learned that the vendor we use to answer support requests and other emails (Zendesk) experienced a security breach," said Pinterest in an email.
Tumblr also urged its users to review their previous email conversations with Zendesk to ensure that there was no account information that the perpetrators could later use in phishing attacks.
Meanwhile, Zendesk CEO Mikkel Svane shed some light the breach.
"We've become aware that a hacker accessed our system this week. As soon as we learned of the attack, we patched the vulnerability and closed the access that the hacker had," said Svane.