Facebook has sealed a security hole that left users' names and profile pictures available to unrelated users.
The vulnerability was first reported by Secfence Technologies researcher Atul Agarwal on the Full Disclosure security mailing list.
Agarwal found that entering an email address and incorrect password into the Facebook log-in screen returned a password incorrect message which contained first name and surname along with a profile photograph.
The researcher suggested that the vulnerability could be used by cyber criminals to match names to mass lists of email addresses. The information could then be used for customised spear phishing operations.
A Facebook spokesperson told V3.co.uk that the issue had been fixed, and that the information is no longer available.
"We have technical systems in place to prevent names and photos showing to unrelated users on log-in, but a recently introduced bug temporarily prevented these from working as intended," the company said. "We remedied the situation swiftly."
Facebook has been under intense pressure from privacy groups, and has spent much of 2010 shoring up its security and providing a clearer explanation of what data is shared and how users can lock down their information.
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