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Windows DRM-Protected Files Used To Decloak Tor Browser Users (bleepingcomputer.com)

Posted by BeauHD on from the coordinates-on-a-map dept.

An anonymous reader writes from a report via BleepingComputer: Downloading and trying to open Windows DRM-protected multimedia files can deanonymize Tor Browser users and reveal their real IP addresses, security researchers from Hacker House have warned. On Windows, multimedia files encoded with special Microsoft SDK will automatically open an IE window and access a URL to check the file's license. Since this request is sent outside of the Tor Browser and without user interaction, this can be used to ping law enforcement servers and detect the user's real IP address and other details. For example, law enforcement could host properly signed DRM-protected files on sites pretending to host child pornography. When a user would try to view the file, the DRM multimedia file would use Internet Explorer to ping a server belonging to the law enforcement agency. The same tactic can also be used to target ISIS militants trying to view propaganda videos, illegal drug and weapons buyers trying to view video product demos, political dissidents viewing news videos, and more. A video of the attack is available here.

3 of 150 comments (clear)

  1. Quick Workaround by gavron · · Score: 4, Interesting

    1. Determine which TOR-nodes you're talking to. (Netstat or Ethereal)
    2. Remove default route through your ISPs router
    3. Add specific routes to the /32s the TOR-nodes are on through the ISP router

    Traffic routed through TOR will work fine.
    Traffic going outside of TOR will fail except for the local network (your home or office LAN).

    E

  2. Re:I'm ok with this behavior in those use cases by Anonymous Coward · · Score: 5, Interesting

    "First they came for the kiddy fiddlers, and no one objected..." Then a month from now, the FBI is ordered to embed these bugs in videos of services at mosques, and videos of anti-Trump protests, and videos of CNN interviews, and seed them all around the internet to build The Bigly List of Brown People and Dissenters.

    In the Bush era, I would have laughed this off as a slippery slope argument. In present times, knowing what Snowden has taught us and watching the current political climate, I don't see it as a laughing matter.

  3. Re:Ask OS makers next? by Anonymous Coward · · Score: 4, Interesting

    Next? There's a high likelihood this is already happening in Windows 10. Every time you open a file, Windows 10 is sending unknown "telemetry" back to the mother ship. Those Windows Defender and Microsoft Security Essentials updates you get every day? They're hash lists. You can bet your ass those lists contain more than just virus signatures, and matches are being recorded somewhere.