4 ms·
Can’t an attacker now man in the middle anyone who hasn’t connected to github since the host key was rolled?
by __turbobrew__ 4y ago
Can’t an attacker now man in the middle anyone who hasn’t connected to github since the host key was rolled?
- paxys 4y agoUnless they can also hijack the github.com domain, no.
- aaomidi 4y agoThat’s not that hard tbh. So many attacks.
- __turbobrew__ 4y agoBut if you are doing git operations using SSH instead of HTTPS then you aren’t checking domain certs?
- paxys 4y agoIt's not about the certs. To execute a man-in-the-middle attack the attacker has to literally put themselves in the middle of the route your packet takes to get to github's servers and intercept it.
- __turbobrew__ 4y agoSure, there are many ways an attacker can do that. Not trusting your IP transit is kind of the whole reason for encryption in the first place. 1. Various DNS hijacking and cache poisoning attacks 2. three letter agencies in meet me rooms 3. Exploited/hacked routers 4. Wifi hot spots
- deleted 4y ago[deleted]
- nextaccountic 4y agoYes, and that's how malware ends up in npm and other package managers
- raggi 4y agoIt could be worse, the user has the old rsa host key present alongside newer ed / ecdsa keys, they may never rotate out the rsa one. A future mitm simply only advertises the rsa key, and mitm passes. Users will need to actively remove the old rsa key in order to be safe. It's my first question, and a colleague suggested that they believe that the private key was not seen, however, I don't see that in the post - unless I'm missing it - and I really want this stated very clearly somewhere.
- __turbobrew__ 4y ago> Users will need to actively remove the old rsa key in order to be safe Yea that is my read on it as well. If that is true this is much more severe than the blog post suggests.
- NieDzejkob 4y agoI tested this and on a new enough OpenSSH client, the RSA key gets replaced using the mechanism described here: https://lwn.net/Articles/637156/ https://lwn.net/Articles/637156/ (if you connect using a key other than RSA). To be honest, I'd expect something like this to be mentioned in the announcement.
- creamyhorror 4y agoAssuming the user connects to Github first instead of a MitM attacker spoofing Github.