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Researcher Finds Tor Exit Node Adding Malware To Downloads
Trailrunner7 writes: A security researcher has identified a Tor exit node that was actively patching binaries users download, adding malware to the files dynamically. The discovery, experts say, highlights the danger of trusting files downloaded from unknown sources and the potential for attackers to abuse the trust users have in Tor and similar services. Josh Pitts of Leviathan Security Group ran across the misbehaving Tor exit node while performing some research on download servers that might be patching binaries during download through a man-in-the middle attack.
What Pitts found during his research is that an attacker with a MITM position can actively patch binaries–if not security updates–with his own code. In terms of defending against the sort of attack, Pitts suggested that encrypted download channels are the best option, both for users and site operators. "SSL/TLSis the only way to prevent this from happening. End-users may want to consider installing HTTPS Everywhere or similar plugins for their browser to help ensure their traffic is always encrypted," he said via email.
What Pitts found during his research is that an attacker with a MITM position can actively patch binaries–if not security updates–with his own code. In terms of defending against the sort of attack, Pitts suggested that encrypted download channels are the best option, both for users and site operators. "SSL/TLSis the only way to prevent this from happening. End-users may want to consider installing HTTPS Everywhere or similar plugins for their browser to help ensure their traffic is always encrypted," he said via email.
And I'm glad the article says everything is just fine and there are no problems. What a relief.
Or check the checksum
Who's to say that your friendly ISP or government agency isn't doing the same? Or even better yet, how about for OS updates.
Last time I checked even my linux *.list files were referencing HTTP hosts rather than HTTPS (not that HTTPS is really much better, when gov't agencies are concerned)
Might make sense to use an SSL-enabled connection and a key that's provided with the distro.
Cloudflare offers a fake SSL service called "Flexible SSL". Cloudfront gets a cert generated with a long list of domains. Users connect to Cloudfront, Cloudflare sets up a secure connection from the user's browser to Cloudflare, acts as a man-in-the-middle, and makes an unencrypted connection to the destination host.
And, of course, there's an exploit for this.
Even if you buy Cloudflare'ss "most secure" option, and have SSL to your own server using your own certificate, you have to give Clouldflare your SSL cert's private keys. Does Clouldflare take responsiblity for the security of your private keys? No.
So do not use Cloudflare for sites which handle any valuable data, such as credit card numbers.
Sorry, "HTTPS everywhere", not "-only" - it tries HTTPS first, which helps with a bunch of sites so you don't have to bookmark the https version specifically, but still falls back to HTTP when needed.
Everyone should use that plugin in normal browsing IMO - it will drive traffic to HTTPS, and really there's no reason for non-HTTPS sites anymore Slashdot are you listening, you HTTP-only weenies?
Socialism: a lie told by totalitarians and believed by fools.
There have been several reports of Bitcoin users that use online wallets and exchanges, even over https, getting MITM attacked when using Tor. They visit the wallet site, get bad certificates but continue anyway, and poof, their Bitcoins in the service are gone and their passwords are known by the attacker. With recent SSL vulnerabilities or clever redirection, the cert errors could be avoided also. For other sites, users can be piped through a "universal phisher" to steal any credentials.
Clearly Tor users are under attack by exit nodes, many of them running automated tools against many web destinations.
Probably varies Linux distro to distro. In Windows, the MSU files are all signed by MS so the download path isn't of issue, since if it is compromised any alterations to the file would break the signature.
Tor provides anonymity. It does not provide authenticity or secrecy, and doesn't pretend to. If you want those things, you should use something else in addition to tor. For example, TLS or SSH might suit your needs.
-- MartinG To mail me: echo kewyjlcxyzvjfxbqwh | tr bcefhjklqvwxyz
See SNI and StartSSL
Michael J. Ryan - tracker1.info