A serious vulnerability in the freshly released Firefox 16 caused Mozilla to temporarily withdraw the web browser from the official download page. Since the security flaw does not affect the previous release of the browser, Firefox 15.0.1 is up again.
The uncovered flaw could allow malicious sites to identify the websites visited by users and access the URL or URL parameters. Mozilla notes that they have no knowledge of the vulnerability being exploited in the wild.
At the moment, the development team is preparing a chemspill for both the desktop and the mobile version of the browser. A patched Firefox (16.0.1) should arrive today.
Mozilla recommends downgrading to Firefox 15.0.1, since it is not affected by the bug (downloads are available from Softpedia). Alternatively, users can wait for the update, which is applied automatically.
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