SAN FRANCISCO (AP) — Facebook is getting an unwelcome look at the shady side of the hacking culture that CEO Mark Zuckerberg celebrates.
Intruders recently infiltrated the systems running the world's largest online social network but did not steal any sensitive information about Facebook's more than 1 billion users, according to a blog posting Friday by the company's security team.
The unsettling revelation is the latest breach to expose the digital cracks in a society and an economy that is storing an ever-growing volume of personal and business data online.
The news didn't seem to faze investors. Facebook Inc.'s stock dipped 10 cents to $28.22 in Friday's extended trading.
The main building at Facebook's Menlo Park, Calif., headquarters lists its address as 1 Hacker Way. From there, Facebook serves as the gatekeeper for billions of potentially embarrassing photos and messages that get posted each month.
This time, at least, that material didn't get swept up in the digital break-in that Facebook said it discovered last month. The company didn't say why it waited until the afternoon before a holiday weekend to inform its users about the hack.
It was a sophisticated attack that also hit other companies, according to Facebook, which didn't identify the targets.
"As part of our ongoing investigation, we are working continuously and closely with our own internal engineering teams, with security teams at other companies, and with law enforcement authorities to learn everything we can about the attack, and how to prevent similar incidents in the future," Facebook wrote on the blog.
Online short-messaging service Twitter acknowledged being hacked earlier this month. In that security breakdown, Twitter warned that the attackers may have stolen user names, email addresses and encrypted passwords belonging to 250,000 of the more than 200 million accounts set up on its service.
Late last month, both The New York Times and The Wall Street Journal — two of the three largest U.S. newspapers — said they were hit by China-based hackers believed to be interested in monitoring media coverage of topics that the Chinese government deemed important.