Facebook, the biggest social-networking company, is working to fix a security flaw that let people view other users' private photos, including those of chief executive Mark Zuckerberg.
The bug enabled anyone to view a "limited number" of recently uploaded photos, regardless of a person's privacy settings, the company said. Facebook shut the affected system and will restore it after the glitch is fixed. Photos of Zuckerberg were published anonymously on the web, reports said.
"The privacy of our user's data is a top priority for us, and we invest significant resources in protecting our site and the people who use it," the California-based company said.
Facebook, which has more than 800 million users, is taking steps to improve privacy after agreeing last month to settle complaints by the Federal Trade Commission that it failed to protect user data or disclose how it could be used.
In a blog posting at the time, Zuckerberg said the company should have been more vigilant in protecting users' privacy and that Facebook had made "a bunch of mistakes".
Blogs including Cnet's ZDnet posted photos from Zuckerberg's personal collection.