The Computer Emergency Response Team of Ukraine (CERT-UA) reports about a new campaign dubbed "SickSync," launched by the UAC-0020 (Vermin) hacking group in attacks on the Ukrainian defense forces.
Honestly, I didn’t think about vulnerability in SyncThing when I read the article. But I wondered why defense forces would have p2p open on their networks.
Not necessarily. Torrent is a way to find a peer for direct connection or via a relay (of course that is more than that). Syncthing, even using a relay server, requires some ports available for at least outbound connection (22000 TCP/UDP or whatever port the relay is using). This should not be possible in a medium security network, let alone a defense network.
I don’t know if syncthing works without a direct connection (to the peer or relay, something like transport via http proxy).
It does. It has hole punching incorporated into the protocol. So as long as it can get to the internet, it can use coordination servers and do double hole punching so that they can talk to each other
Interesting. I didn’t know that syncthing does hole punching.
From a defense perspective, how would this work with an enterprise firewall, with UDP/TCP only allowed to specific destinations or specific sources. Example: only the internal DNS relay server can access 53/UDP and only the internal proxy server can access 80/443. What I mean is in a network with a very closed firewall, how would Syncthing be able to connect with peers?
Bestbet would probably be block on an application level. I swapped to bitwarden since syncthing wasn’t liked by the AV on my work pc and I was using it to sync my password db.
Honestly, I didn’t think about vulnerability in SyncThing when I read the article. But I wondered why defense forces would have p2p open on their networks.
When you say P2P you think torrents. But syncthing have rendezvou helpers to facilitate connections without seeing any data.
Not necessarily. Torrent is a way to find a peer for direct connection or via a relay (of course that is more than that). Syncthing, even using a relay server, requires some ports available for at least outbound connection (22000 TCP/UDP or whatever port the relay is using). This should not be possible in a medium security network, let alone a defense network. I don’t know if syncthing works without a direct connection (to the peer or relay, something like transport via http proxy).
It does. It has hole punching incorporated into the protocol. So as long as it can get to the internet, it can use coordination servers and do double hole punching so that they can talk to each other
Interesting. I didn’t know that syncthing does hole punching.
From a defense perspective, how would this work with an enterprise firewall, with UDP/TCP only allowed to specific destinations or specific sources. Example: only the internal DNS relay server can access 53/UDP and only the internal proxy server can access 80/443. What I mean is in a network with a very closed firewall, how would Syncthing be able to connect with peers?
If the firewall was properly locking down servers to functions then it shouldn’t work. But if it has general Web access sync thing is very resilient
This is the reason people use sync thing and recommend it, it’s really hard to kill
Bestbet would probably be block on an application level. I swapped to bitwarden since syncthing wasn’t liked by the AV on my work pc and I was using it to sync my password db.