Stephen Fry has quit Plaxo after he became annoyed that the social networking site was revealing what he sees as too many personal details with anyone visiting the site - as opposed to designated contacts.
Plaxo, which was co-founded by Napster co-creator Sean Parker, maintains an online address book and social networking service. The service has fully configurable privacy settings, but Fry believes the default settings are sharing rather more information than he's comfortable with.
In a message on Twitter last Friday, Fry complained that Plaxo was "distributing my details to every casual passerby" and not just his online contacts.
Separately, a Reg reader told us on Thursday that anyone with an account can freely browse all the personal information held on Plaxo, including their mobile number and addresses as well as who users have logged as contacts.
We asked Rik Ferguson, a security researcher at Trend Micro, to help us investigate this on Friday morning, prior to Fry's fall-out with the social networking site.
Ferguson responded that Plaxo appeared to be operating normally - i.e. it's sharing only information that users have chosen to share.
Our tipster, who asked to remain anonymous, accepted this diagnosis while noting that the design of Plaxo could give rise to privacy problems. "If this really is by design, then fair enough. I was just staggered at the amount of data available by trawling through Plaxo and the contact details and contacts for lots of seemingly significant people. Someone could easily build a very interesting correlated database using the info that seems publicly visible."
Fry was put out that anyone who logged into Plaxo was able to see his mobile phone number and postal address. With other social networking sites such as LinkedIn and Facebook, only a member's contacts can see this kind of information.
Plaxo spokesman John McCrea responded that Fry himself had permitted logged-in users to see this information. He denied there was any breach in the security of the service.
"As best I can tell, what's happened is that one user (albeit a rather prominent one!) was surprised to find that the sharing settings he'd previously applied to some of his personal info were more public than he'd intended," McCrea told The Guardian.
"We certainly have not made any changes to settings, features or policies that would make anyone's personal information more widely available than it had previously been."
It's not the first time the actor and celebrated brain-box has become upset with a social networking service. Last month, Fry briefly threatened to quit Twitter, where he is followed by over a million people, after a fan criticised his updates to the social networking site as "boring."
Fry's detractor quickly apologised, while the comedian's many supporters urged him to keep on tweeting, prompting Fry to change his mind and stick with the micro-blogging site. ®