Don’t Trust Private Browsing Modes For True Privacy

Don’t Trust Private Browsing Modes For True Privacy

Every major browser has an “Incognito Mode”, “Private Browsing”, “inPrivate” or something similar — a switch that supposedly covers your tracks, at least on your computer. But security researchers have found many holes in the armour that privacy modes supposedly provide.

Ars Technica decompiles a paper from Stanford and Carnegie Mellon researchers (direct PDF link) that tests the security of private browsing modes in Internet Explorer, Firefox, Chrome and Safari, and finds them all seriously lacking.

What’s wrong with private browsing? Most significantly, it’s add-ons and plug-ins that betray privacy. Adobe’s Flash has often been cited for cookies that don’t wipe clean, but it’s also browser-specific add-ons that can betray where a browser has been. Those browser that don’t allow add-ons to run in their private modes also don’t protect against “suitably crafted sites (that) could trace visitors between private and non-private sessions”.

All a good reminder that while there are ways to browser without leaving a trace, you shouldn’t count on your browser’s privacy mode to do much more than protect you against the most basic of inquiries into what you’ve been doing.

Private browsing: it’s not so private [Ars Technica]


  • Apart from Sandboxie, for increased privacy I would try to use portable-firefox from a flash drive.

    In my opinion, for a truly “disposeable firefox” one could:
    1. Setup portable-firefox with your bookmarks, addons etc
    2. Copy entire portable-firefox to backup location (on same thumb drive)
    3. Surf webpages
    4. Delete entire working portable-firefox folder when finished surfing.
    5. Restore portable-firefox folder from backup

    Of course a batch script would be perfect for this. I have experimented with this ages ago and its slow because of the restoring part.

    Deleting the cache and restoring the profile (to prevent web bugs like hijacks) would be a lot lot quicker than restoring the portable-firefox folder. On this subject there is;

    Will try to do a script thats quick to use sometime. WIGATI (When I get around to it 🙂


    • A RAM Drive would make the Portable Firefox worth the effort.

      Perhaps with xmarks installed, you do not need to store the profile.

      Might want to update the Original Source (zip or 7z) with the latest updates etc.

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