Browser privacy settings often fail web usersPrivate browsing modes leak data

12 August 2010

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The private browsing features on Internet Explorer, Firefox, Chrome and Safari are not as secure as users think, according to new research.

That’s one of the key findings to emerge from security boffins at Stanford University and the Carnegie Mellon University in the US.

Browser privacy features prevent the history of websites visited and cookies from being stored on your computer, and accessed later by other users. The idea is that because personal information isn't stored, privacy features can also help protect web users from hacking attempts - both locally on your PC and over the web.

Feature weaknesses

However, the experts discovered that there were multiple weaknesses in private web browsing modes that could expose your web browsing history to hackers.

They said the way they were set up encouraged the leaking of information about the websites that users had visited, which meant traces of leaked data could still be picked up by attackers, even if the private browsing features were in use.

This leaking of data, the researchers said, allows ‘a local attacker to completely defeat the benefits of private browsing mode and go on to reconstruct a user’s web browsing history’.

Browser extensions and plug-ins

They found that popular web-browser extensions and plugins could further expose private browsing flaws, so that ‘even if a browser adequately implements private browsing, an extension can completely undermine its privacy guarantees’.

‘Our results suggest that current private implementations provide privacy against some local and web attackers, but can be defeated by determined attackers. Further research was needed to ‘design stronger privacy guarantees without degrading the user experience,’ the researchers concluded.

If you'd like to make sure your PC's safe from attackers, take a look at Which? Best Buy security software 

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